Mental Illness and/or Mental Health? Investigating Axioms of the Complete State Model of Health

Journal of Consulting and Clinical Psychology
Copyright 2005 by the American Psychological Association
2005, Vol. 73, No. 3, 539 –548
0022-006X/05/$12.00
DOI: 10.1037/0022-006X.73.3.539
Mental Illness and/or Mental Health? Investigating Axioms of the
Complete State Model of Health
Corey L. M. Keyes
Emory University
A continuous assessment and a categorical diagnosis of the presence (i.e., flourishing) and the absence
(i.e., languishing) of mental health were proposed and applied to the Midlife in the United States study
data, a nationally representative sample of adults between the ages of 25 and 74 years (N
3,032).
Confirmatory factor analyses supported the hypothesis that measures of mental health (i.e., emotional,
psychological, and social well-being) and mental illness (i.e., major depressive episode, generalized
anxiety, panic disorder, and alcohol dependence) constitute separate correlated unipolar dimensions. The
categorical diagnosis yielded an estimate of 18.0% flourishing and, when cross-tabulated with the mental
disorders, an estimate of 16.6% with complete mental health. Completely mentally healthy adults
reported the fewest health limitations of activities of daily living, the fewest missed days of work, the
fewest half-day work cutbacks, and the healthiest psychosocial functioning (low helplessness, clear life
goals, high resilience, and high intimacy).
Keywords: subjective well-being, happiness, depression, mental health, mental illness, mental disorder,
psychopathology
Health is not simply the absence of disease: it is something positive. . .
study, I examine three descriptive questions to investigate the use
—Henry Sigerist, Medicine and Human Welfare
of the mental health diagnosis. What is the point prevalence of
mental health (i.e., flourishing) and of complete mental health (i.e.,
There exists no standard by which to measure, diagnose, and
flourishing and free of 12-month mental disorder)? Does the risk
study the presence of mental health; science, by default, portrays
of Diagnostic and Statistical Manual of Mental Disorders (3rd ed.,
mental health as the absence of psychopathology. This study
rev.; DSM–III–R; American Psychiatric Association, 1987) 12-
introduces self-report measures of mental health for use in the
month mental disorders decrease as mental health increases? Does
general population that may also be useful with clinical patients. It
psychosocial functioning (e.g., perceived helplessness) improve as
summarizes the scales and dimensions of subjective well-being—
the level of mental health increases?
the evaluations and declarations that individuals make about the
quality of their lives—that are used as measures of the symptoms
of mental health. Mental health is conceived of as a complete state
Health or Illness? Health and Illness?
in which individuals are free of psychopathology and flourishing
Health has been alleged to be a complete state consisting of not
(Keyes, 2002, 2003a, 2003b) with high levels of emotional, psy-
merely the absence of illness but the presence of something pos-
chological, and social well-being.
itive (Ryff & Singer, 1998; Sigerist, 1941; World Health Organi-
Because of skepticism of the benefits of studying mental health,
zation, 1948). The de facto conception of mental health is psychi-
there are to my knowledge literally no studies of the latent struc-
atric: Individuals are either mentally ill or presumed mentally
ture or the use of regarding mental health as more than the absence
healthy. This position rests on the untested assumption that mea-
of psychopathology. In this study, I investigate two axioms of the
sures of mental illness and health form a single bipolar dimension.
complete state model of health. First, rather than forming a single
Several reasons justify the primacy of the dichotomous, psychiatric
bipolar dimension, health and illness are correlated unipolar di-
view of mental health. First, at the birth of the National Institute of
mensions that, together, form a complete state of (mental) health.
Mental Health, the field of psychopathology was better developed
Second, the presence of mental health is presumed to be the
empirically than the mostly theoretical literature of clinical and
summum bonum of personal functioning and social value. In this
personality psychology that informed conceptions of positive men-
tal health (Jahoda, 1958; Smith, 1959). Second, evidence is now
overwhelming that individuals free of major depression, for ex-
Corey L. M. Keyes, Department of Sociology and Department of
ample, function better and are more productive than depressed
Behavioral Sciences and Health Education of the Rollins School of Public
individuals (Sartorius, 2001). Third, evidence is indisputable that
Health, Emory University.
mental illness is a serious public health issue. Mental disorders are
This research was supported by membership in the John D. and Cathe-
prevalent (often comorbid), recur throughout the life span, are
rine T. MacArthur Foundation Research Network on Successful Midlife
costly to treat, and cause premature mortality when untreated
Development (Director: Orville Gilbert Brim).
(Garrison, Schluchter, Schoenbach, & Kaplan, 1989; Greenberg,
Correspondence concerning this article should be addressed to Corey
L. M. Keyes, Emory University, Room 225 Tarbutton Hall, 1555 Dickey
Stiglin, Finkelstein, & Berndt, 1993; Kessler et al., 1994; Keyes &
Drive, Atlanta, GA 30322. E-mail: corey.keyes@emory.edu
Lopez, 2002; U.S. Public Health Service, 1998, 1999).
539

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540
KEYES
The burden of mental illness now deflects attention from the
The diagnosis of states of mental health was modeled after the
question and significance of mental health. However, mental
DSM–III–R approach to diagnosing MDE (Keyes, 2002). A diag-
health remains a nascent public health issue, because the vast
nosis of depression is made when an individual reports at least one
majority of the U.S. population is free of mental illness (see
symptom from the anhedonia cluster and four or more symptoms
Kessler & Zhao’s, 1999, study).1 Are all individuals without
of malfunctioning. Thus, to be diagnosed with MDE, individuals
mental disorders leading equally productive and healthy lives, and
must exhibit at least five of nine possible symptoms, which is
are they leading more productive and healthier lives than the
55.6% or more of the total possible symptoms. Similarly, this
mentally ill? Answers to this question require investigation of the
article adopts the criteria outlined in Keyes’s (2002) study, in
structural axiom of the complete health model, which is supported
which individuals must exhibit at least 7 of the possible 13 symp-
by several lines of thought and research.
toms of subjective well-being, which is 53.8% or more of the total
First, many individuals otherwise free of mental disorder do not
possible symptoms of mental health. Specifically, to be diagnosed
feel healthy or function well. Nearly half of adults receive mental
as flourishing in life, individuals must exhibit high levels on one of
health services annually because a mental health problem is in-
the two scales of hedonic well-being and high levels on 6 of the 11
ferred, meaning that there was no diagnosable disorder (Regier et
scales of positive functioning. To be diagnosed as languishing in
al., 1993). Second, positive and negative affects form two corre-
life, individuals must exhibit low levels on one of the two scales of
lated factors (Bradburn, 1969; Tellegen, Watson, & Clark, 1999;
hedonic well-being and low levels on 6 of the 11 scales of positive
Watson & Tellegen, 1985). Thus, for example, individuals who
functioning. Adults who are moderately mentally healthy do not fit
may not feel sad—a defining feature of depression— do not nec-
the criteria for either flourishing or languishing in life. As with the
essarily experience high levels of happiness. Third, select mea-
diagnosis of major depression, symptoms of hedonia are essential
sures of subjective well-being and common mental illnesses form
for the diagnosis of mental health; individuals must exhibit a high
distinct, correlated factors (Headey, Kelley, & Wearing, 1993,
level of satisfaction or a high level of positive affect.
focused on life satisfaction, happiness, anxiety, and depressive
In addition, the DSM–IV–TR Axis V (i.e., global assessment of
symptoms; Keyes & Ryff, 2003, focused on psychological well-
functioning [GAF] assessment) is a continuous variable approach
being and depressive symptoms). Thus, the structural axiom sug-
that is proffered in this article as a second diagnostic approach for
gests that scholars and clinicians must take into account both
mental health. Here, the items and scales that measure each mental
mental illness and mental health, in which mental health is some-
health cluster are summed together and coded into 10-point range
thing positive.
categories. Unlike the categorical diagnosis, the continuous assess-
ment of mental health does not mirror any specific DSM–III–R
mental illness. Hedonic well-being obviously remains part of the
A Conception and Operationalization of Mental Health
assessment of mental health, but it is not considered an essential
symptom to have a high level of mental health. Instead, high-level
The Surgeon General defined mental health as “. . . a state of
mental health requires individuals to report high levels on most (or
successful performance of mental function [italics added], resulting
all) measures of subjective well-being, whereas the categorical
in productive activities, fulfilling relationships with people, and
diagnosis of flourishing requires only high levels on over half of
the ability to adapt to change and to cope with adversity” (U.S.
the measures. The continuous assessment of mental health, there-
Public Health Service, 1999, p. 4). Mental health is clearly some-
fore, provides a more holistic assessment of mental health than the
thing positive, but what exactly composes this positive state of
categorical diagnosis, and it is used here to assess whether results
mind? Keyes (2002) defined mental health as a syndrome of
depend on the diagnosis or the assessment.
symptoms of hedonia and positive functioning, operationalized by
There also remains skepticism regarding the scientific and ap-
measures of subjective well-being—individuals’ perceptions and
plied value of measuring and classifying individuals in terms of
evaluations of their lives and the quality of their functioning in life.
their mental health. According to Mechanic (1999), “Although the
Nearly half a century of research has yielded as many as 13
concept of positive mental health is one worth keeping in mind, it
symptoms (i.e., measures) of mental health that, when factor
is not very helpful in classifying different persons, groups, or
analyzed, represent either the latent structure of hedonic well-
populations” (p. 2). Whether Mechanic’s claim is warranted is an
being or eudaimonic well-being (Keyes, Shmotkin, & Ryff, 2002;
empirical question that has yet to be studied. Therefore, and as
Keyes & Waterman, 2003; McGregor & Little, 1998; Ryan &
displayed in Figure 1, I also investigate the functioning axiom of
Deci, 2001; Waterman, 1993). Table 1 presents the proposed
the complete health model in this study. Complete mental health
cluster of symptoms and diagnostic criteria for mental health (i.e.,
(i.e., the absence of mental illness and presence of flourishing) is
flourishing). It is noteworthy that, without intending it, subjective
more functional and adaptive than moderate mental health or pure
well-being research yielded clusters of mental health symptoms
languishing (i.e., absence of mental illness). In turn, pure languish-
that mirror the cluster of symptoms used in the Diagnostic and
ing is as dysfunctional as an episode of pure mental illness (i.e.,
Statistical Manual of Mental Disorders (4th ed., text rev.; DSM–
presence of mental illness but also the presence of moderate
IV–TR; American Psychiatric Association, 2000) to diagnose ma-
mental health or maybe even flourishing). Last, complete mental
jor depressive episode (MDE). In the same way that depression
requires symptoms of anhedonia, mental health is proposed to
consist of symptoms of hedonia, or emotional vitality and positive
1 Data from the National Comorbidity Study indicate that one half of the
feelings toward one’s life. Moreover, in the same way that major
economically viable population (i.e., ages 15–54 years) will remain free of
depression consists of symptoms of malfunctioning, mental health
mental illness over its lifetime and about 70% annually does not fit the
is proposed to consist of symptoms of positive functioning.
DSM–IV–TR criteria for most mental illnesses.

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COMPLETE STATE MODEL OF HEALTH
541
Table 1
Categorical Diagnosis of Mental Health (i.e., Flourishing)
Diagnostic criteria
Symptom description
Hedonia: requires high level on at least one
1. Regularly cheerful, in good spirits, happy, calm and
symptom scale (Symptoms 1 or 2)
peaceful, satisfied, and full of life (positive affect
past 30 days)
2. Feels happy or satisfied with life overall or
domains of life (avowed happiness or avowed life
satisfaction)a
Positive functioning: requires high level on
3. Holds positive attitudes toward oneself and past life
six or more symptom scales (Symptoms 3–13)
and concedes and accepts varied aspects of self
(self-acceptance)
4. Has positive attitude toward others while
acknowledging and accepting people’s differences
and complexity (social acceptance)
5. Shows insight into own potential, sense of
development, and open to new and challenging
experiences ( personal growth)
6. Believes that people, social groups, and society
have potential and can evolve or grow positively
(social actualization)
7. Holds goals and beliefs that affirm sense of
direction in life and feels that life has a purpose
and meaning ( purpose in life)
8. Feels that one’s life is useful to society and the
output of his or her own activities are valued by or
valuable to others (social contribution)
9. Exhibits capability to manage complex
environment, and can choose or manage and mold
environments to suit needs (environmental mastery)
10. Interested in society or social life; feels society and
culture are intelligible, somewhat logical,
predictable, and meaningful (social coherence)
11. Exhibits self-direction that is often guided by his or
her own socially accepted and conventional internal
standards and resists unsavory social pressures
(autonomy)
12. Has warm, satisfying, trusting personal relationships
and is capable of empathy and intimacy ( positive
relations with others)
13. Has a sense of belonging to a community and
derives comfort and support from community
(social integration)
a Life domains may include employment and marriage or close interpersonal relationship (e.g., parenting).
illness (i.e., presence of mental illness and absence of mental
ter than moderately mentally healthy individuals, who in turn
health—languishing) should be more dysfunctional than a pure
should function better than languishing individuals.
mental illness. These predictions may only apply to the most
common mental disorders (e.g., anxiety and mood) rather than the
Method
less common but more severe psychotic disorders. Nonetheless,
Sample
the functioning axiom predicts that within the realm of mental
health, completely mentally healthy individuals will function bet-
Data are from the Midlife in the United States (MIDUS) survey con-
ducted by the MacArthur Foundation’s Research Network on Successful
Midlife Development. The MIDUS is a national probability sample, drawn
with random digit dialing procedures, that consisted of English-speaking,
noninstitutionalized adults, age 25–74 years, who resided in the 48 con-
tiguous states and whose household included at least one telephone. The
first stage of the multistage sampling design selected households with
equal probability via telephone numbers. Disproportionate stratified sam-
pling was used at the second stage to select respondents. The sample was
Figure 1.
Predictions of psychosocial functioning from the complete state
stratified by age and gender, with oversampling of men between the ages
model of mental health. Signs are reversed for negative outcomes. Pure
of 65 and 74 years. Working nonhousehold (e.g., business) numbers were
mental illness
any 12-month mental disorder without languishing; pure
eliminated by definition, and working numbers that were unsuccessfully
languishing
any languishing without any 12-month mental disorder.
contacted 10 times were also eliminated.

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542
KEYES
The MIDUS survey complied with Institutional Review Board stan-
good spirits, (c) extremely happy, (d) calm and peaceful, (e) satisfied, and
dards, and interviewers read a standard informed consent protocol at the
(f) full of life. The internal reliability of the positive affect scale was .91.
beginning of the telephone interview. Adults who agreed to participate
Moreover, respondents were asked to “rate their life overall these days” on
were administered a computer-assisted telephone interview that lasted 45
a scale ranging from 0 (worst possible life overall) to 10 (best possible life
min on average and were then mailed two questionnaire booklets that
overall ).
required about 1.5 hr on average to complete. All participants were offered
Respondents also completed Ryff’s (1989) scales of psychological well-
$20 and a copy of a final study monograph as incentives for participation.
being and Keyes’s (1998) scales of social well-being. The psychological
With a response rate of 70% for the telephone phase and a response rate of
well-being scales reflect how much individuals are thriving in their private,
87% for the self-administered questionnaire phase, the overall response
personal lives. The scales, with a representative item in parentheses, are as
rate was 61% with a sample size of 3,032 respondents. Field procedures
follows: self-acceptance (“I like most parts of my personality”), positive
lasted approximately 13 months and were begun in 1994 and concluded in
relations with others (“Maintaining close relationships has been difficult
1995.
and frustrating for me”), personal growth (“For me, life has been a
Descriptive analyses are based on the weighted sample to correct for
continual process of learning, changing, and growth”), purpose in life (“I
unequal probabilities of household and within household respondent se-
sometimes feel as if I’ve done all there is to do in life”), environmental
lection. The sample weight poststratifies the sample to match the propor-
mastery (“I am good at managing the responsibilities of daily life”), and
tions of adults according to age, gender, education, marital status, race,
autonomy (“I tend to be influenced by people with strong opinions”). The
residence (i.e., metropolitan and nonmetropolitan), and region (northeast,
measures of social well-being operationalize how much individuals see
midwest, south, and west) on the basis of the October 1995 Current
themselves thriving in their public, social life. The scales, with a repre-
Population Survey (see Keyes et al.’s, 2002, study for the demographic
sentative item in parentheses, are as follows: social-acceptance (“People do
characteristics of the MIDUS sample). Findings were unchanged by
not care about other peoples’ problems”), social actualization (“Society is
whether the sample was weighted; all descriptive analyses present the
not improving for people like me”), social contribution (“My daily activ-
findings based on the weighted sample. The sampling design involved
ities do not create anything worthwhile for my community”), social coher-
some complexities that could introduce design effects that inflate standard
ence (“I cannot make sense of what’s going on in the world”), and social
error estimates. However, simulations with jackknife repeated replications
integration (“I feel close to other people in my community”).
(see Kish & Frankel’s, 1974, study) on an array of variables revealed very
Each scale of positive functioning (i.e., psychological and social) con-
small standard error inflation of design-based estimates, eliminating the
sisted of three items with a relative balance of positive and negative items
need to adjust statistical tests for design effects in these data.
and were self-administered. Respondents indicated whether an item de-
scribed how they functioned on a scale ranging from 1 (strongly agree) to
Measures
7 (strongly disagree). Negative items were reverse coded. The three-item
Mental illness.
The MIDUS used DSM–III–R (American Psychiatric
scales of psychological well-being have shown modest internal consistency
Association, 1987) criteria to diagnose mental illness, which were opera-
(Ryff & Keyes, 1995), whereas the larger, 20-item scales have shown
tionalized by the Composite International Diagnostic Interview Short Form
excellent internal consistency and construct validity (see Ryff’s, 1989,
(CIDI-SF) scales (Kessler, Andrews, Mroczek, Ustun, & Wittchen, 1998).
study). Confirmatory factor analyses also confirmed the proposed six-
Studies have shown that the CIDI-SF has excellent diagnostic sensitivity
factor structure of psychological well-being (Ryff & Keyes, 1995). The
and diagnostic specificity as compared with diagnoses based on the full
internal consistency of the combined 18 items of psychological well-being
CIDI in the National Comorbidity Study (Kessler, DuPont, Berglund, &
in this study was .81. Similarly, the three-item scales of social well-being
Wittchen, 1999). During the telephone interview, the CIDI-SF was used to
have shown modest-to-excellent internal consistency, and the larger item
assess whether respondents exhibited symptoms indicative of (a) MDE, (b)
scales of social well being have exhibited good internal consistency and
generalized anxiety disorder, (c) panic disorder, and (d) alcohol depen-
construct validity (see Keyes’s, 1998, study). Confirmatory factor analyses
dence during the past 12 months (note that all diagnostic criteria used in
supported the proposed five-factor structure of social well-being (Keyes,
this study conform to the criteria outlined in the DSM–IV–TR).
1998). The internal consistency of the combined items of social well-being
Mental health.
As part of the self-administered questionnaire, respon-
in the current study was .81. Table 2 presents the bivariate correlations and
dents indicated how much of the time during the past 30 days—“all,”
descriptive statistics of the continuous (i.e., symptom count) measures of
“most,” “some,” “a little,” or “none of the time”—they felt six symptoms
mental disorder and the summed scale of each type of subjective
of positive affect. The positive affect symptoms were (a) cheerful, (b) in
well-being.
Table 2
Bivariate Correlations and Descriptive Statistics
Variable
1
2
3
4
5
6
7
1. No. depression symptoms
1.00
.33
.32
.07
.33
.26
.16
2. No. generalized anxiety symptoms
1.00
.26
.02a
.19
.22
.15
3. No. panic attack symptoms
1.00
.08
.22
.19
.14
4. No. alcohol dependence symptoms
1.00
.15
.08
.03a
5. Summed scale, emotional well-being
1.00
.54
.36
6. Summed scale, psychological well-being
1.00
.53
7. Summed scale, social well-being
1.00
Range
0–7
0–10
0–6
0–7
1–15
12–42
5–35
M
0.84
0.21
0.37
0.53
11.00
32.90
22.10
SD
2.00
1.10
1.10
1.20
2.20
4.80
4.70
Note.
Correlations are significant at p
.001 (two-tailed).
a Statistically nonsignificant.

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COMPLETE STATE MODEL OF HEALTH
543
Before applying the proposed diagnostic criteria, I divided each scale of
them.” Respondents indicated whether each statement described them “a
emotional, psychological, and social well-being by the number of constit-
lot,” “some,” “a little,” or “not at all.” In this study, I focused analyses on
uent items, standardized, and I computed tertiles. The statistical tertile
the proportion that said that the goal formation, resilience, and intimacy
defines the threshold for high-level (i.e., upper tertile) and low-level (i.e.,
questions described their situation “a lot.”
lower tertile) subjective well-being, because there are no other unambig-
uous thresholds. Thus, like mental disorder, mental health can be viewed as
a deviation from usual functioning, which can be operationalized by the
Results
statistical average or by an ideal standard (e.g., Mechanic, 1999). In this
study, the tertile operationalizes flourishing as above-average functioning
Table 3 reports the indices of fit of confirmatory factor models
and languishing as below-average functioning.
that test different theories of the latent structure of the measures of
Psychosocial functioning.
Respondents indicated whether their health
mental health and mental illness. Three scales served as indicators
limited them “a lot,” “some,” “a little,” or “not at all” from doing any of
of the latent construct of mental health: the summed scales that
nine instrumental activities of daily life. The activities included lifting and
reflected emotional well-being (i.e., satisfaction plus positive af-
carrying groceries, bathing or dressing oneself, climbing several flights of
fect), psychological well-being (i.e., six scales of psychological
stairs, bending (kneeling or stooping), walking more than 1 mile, walking
well-being summed together), and social well-being (i.e., the five
several blocks, walking one block, performing vigorous activity (e.g.,
scales of social well-being summed together). Four summary mea-
running, lifting heavy objects), and performing moderate activity (e.g.,
sures served as indicators of the latent construct of mental illness:
bowling or vacuuming). The internal consistency of the limitation of
the number of symptoms of MDE, generalized anxiety, panic
activity of daily living scale was .91.
Respondents indicated the number of missed and cutback workdays
disorder, and alcohol dependence. The independence model is a
during the past 30 days. Specifically, of the past 30 days, respondents were
baseline in which there were as many latent constructs as measures
asked “How many days were you totally unable to go to work or carry out
of mental health and illness (i.e., each measure reflects an inde-
your normal household work activities because of your physical health or
pendent latent factor). The chi-square statistic and descriptive fit
mental health?” Subsequently, of the past 30 days, and aside from those
indices were very large, indicating that the theory of independence
days they were totally unable to work, respondents were asked, “How
is untenable.
many of the other days did you have to cut back on work or how much you
By comparison, and consistent with the psychiatric model of
got done because of your physical health or mental health?” Follow-up
mental health, Model 2 posits that all measures are caused by a
questions inquired whether the work cutbacks and lost days of work were
single, bipolar latent dimension. The chi-square statistic and de-
due to physical health, to mental health, or to a combination of mental and
scriptive fit indices were markedly improved for the single-factor
physical health. In this study, I focused only on work cutbacks and lost
days due to mental health.
model relative to the independence model. Moreover, the chi-
Respondents also were asked whether they “agreed” or “disagreed” with
square contrast of the independence and single-factor models re-
the following statements: “I often feel helpless in dealing with the prob-
vealed a highly statistically significant reduction of chi-square,
lems of life” and “There is little I can do to change the important things in
suggesting that the single-factor (psychiatric) model was a more
my life.” Analyses focused on the proportion that agreed with the help-
tenable model than the independence model. However, stemming
lessness statements. To measure goal formation, I asked respondents
from the complete state model of health, Model 3—which posits
whether the statements, “I know what I want out of life” and “I find it
that the measures of mental health and mental illness reflect two
helpful to set goals for the near future,” described them “a lot,” “some,” “a
distinct, but uncorrelated, unipolar factors—also had markedly
little,” or “not at all.” Two statements measured respondents’ resilience.
improved fit indices. The chi-square contrast of the independence
First, “When faced with a bad situation, I do what I can to change it for the
and two-factor (orthogonal) model revealed a highly statistically
better.” Second, “I find I usually learn something meaningful from a
difficult situation.” Respondents indicated whether each statement de-
significant reduction of chi-square, suggesting that it too was a
scribed them “a lot,” “some,” “a little,” or “not at all.” Last, intimacy was
more tenable model than the independence model.
measured by asking respondents to indicate whether their (a) spouse or
The final model fully tests the structural axiom of the complete
partner (or other family members) and (b) friends “really care(s) about
health model, that is, measures of mental health and illnesses
Table 3
Maximum Likelihood Estimation of Confirmatory Factor Models of Theories of the Latent
Structure of Continuous Measures of Mental Health and DSM–III–R Mental Disorders
2
/
difference
Latent structure model
2
df
AGFI
CN
RMSEA
AIC
dfdifference
1. Independence
3,388.7
21
.60
25.5
.22
3,402.7
2. Single axis
582.6
14
.88
150.8
.12
687.7
400.9
*
1–2
3. Two axes, orthogonal
557.3
14
.91
157.7
.11
543.6
404.5
*
1–3
4. Two axes, obliquea
162.4
13
.97
511.7
.06
193.5
394.9
*
3–4
Note.
N
2,997. Mental illness measures included measures of the number of symptoms of four mental
disorders: panic disorder, major depressive episode, generalized anxiety, and alcohol dependence; mental health
measures included the summed scales of emotional well-being, psychological well-being, and social well-being.
AGFI
adjusted goodness of fit index; CN
critical N; RMSEA
root-mean-square error of approximation;
AIC
Akaike information criterion.
a The correlation (phi) between latent factors is
.53.
* p
.001.

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544
KEYES
Table 4
Prevalence and Comorbidity of 12-month DSM–III–R Mental Disorders With Mental Health Diagnosis (Sample Weighted)
Categorical diagnosis
Continuous assessment
Mentally
Moderately
Mentally
unhealthy
mentally
healthy
(languishing)
healthy
(flourishing)
0.0–9.9
10.0–19.9
20.0–29.9
30.0–39.9
40.0–49.9
50.0–60.0a
Total
n
511
1,974
547
13
109
477
1,108
962
283
Mental disorder
%
16.9
65.1
18.0
0.4
3.7
16.2
37.5
32.6
9.6
Major depressive episode
n
143
254
26
9
49
11
169
74
12
422
%
28.0
13.4
4.8
69.2
45.0
23.3
15.3
7.7
4.2
14.1
Generalized anxiety
disorder
n
54
41
2
5
21
34
30
6
2
98
%
10.6
2.2
0.4
41.7
19.3
7.1
2.7
0.6
0.7
3.3
Panic disorder
n
80
119
5
4
25
60
72
40
3
204
%
15.7
6.3
0.9
30.8
22.9
12.6
6.5
4.2
1.1
6.9
Alcohol dependence
n
48
134
15
2
9
38
87
54
5
194
%
9.4
6.8
2.7
15.4
8.3
8.0
7.8
5.6
1.8
6.6
Comorbidityb
n
84
107
4
7
32
56
71
24
3
193
%
16.4
5.4
0.7
53.8
29.4
11.7
6.4
2.5
1.1
6.5
Note.
For the separate tests of the association of each mental health diagnosis (categorical and also continuous) with each mental illness diagnosis, p
.002 (two-tailed) for all chi-square tests.
a All separate scales of each type of subjective well-being were summed together to form an overall score, and the overall scores were recoded to reflect
a total score ranging from 0 to the highest score, which was 60.8; because only three scores exceeded 60, and not even by a full point, those three scores
were top coded into the 50 – 60 category.
b Two or more (maximum
4) mental disorders during the past 12 months.
constitute separate latent factors, and the two latent factors are
approximate midpoint of the continuous assessment (i.e., 30.0 –
correlated. The chi-square contrast of the two-factor (orthogonal)
39.9). Although few Americans were languishing—about 17%
Model 3 and the two-factor (oblique) Model 4 revealed a highly
according to the categorical diagnosis—it is important to note that
statistically significant reduction of chi-square, suggesting that the
nearly as many Americans were mentally unhealthy (i.e., languish-
correlated two-factor model was the most tenable model of the
ing) as were mentally healthy (i.e., flourishing). Similarly, al-
structure of mental health and illness. Moreover, the fit indices for
though less than 1% fell into the lowest range of the continuous
Model 4 suggested that it was an excellent fitting model to these
assessment (i.e., 0.0 –9.9), a combined total of just over 20% fell
data. The adjusted goodness-of-fit index was .97, the critical N was
below the approximate midpoint, with continuous scores at 29.9 or
twice as large as the recommended cutpoint of 200, and the
lower.
root-mean-square error of approximation and Akaike information
Table 4 also reports the association of the four DSM–III–R
criterion were smaller than for Model 3. The correlation between
mental disorders and their comorbidity with the mental health
the latent factor of mental illness and mental health was –.53. The
diagnoses. Whether I used the categorical diagnosis or continuous
standardized loadings of all mental health indicators on their latent
assessment, the pattern of results is unequivocal: Flourishing in-
factor were .60 or higher, and the standardized loadings of the
dividuals were at the lowest risk of any of the four 12-month
mental illness measures on their latent factor were .50 or higher,
mental illnesses or their comorbidity. Conversely, and because
except for alcohol dependence, which was .12.2 In sum, data
causality may operate in the other direction, individuals with any
strongly support the structural axiom hypothesis; the theory that
of the four mental disorders were at a very low risk of flourishing.
the measures of mental health and mental illness constitute sepa-
Moreover, the relationship of mental illness and mental health
rate, correlated axes provides the best fitting model to these data.
represents a gradient; the prevalence of each mental illness de-
Table 4 reports the prevalence of mental health as diagnosed
categorically and assessed continuously. Only 18% fit the categor-
creased as level of mental health increased. For example—and
ical diagnosis of flourishing. Moreover, only 9.6% fit into the
highest range of the continuous assessment of mental health (i.e.,
2 The findings reported here include alcohol dependence as an indicator
50 – 60), which was the fourth most prevalent range of mental
of mental illness because reestimation of the two-factor (oblique) model
health scores. Rather, most Americans, roughly 6 in 10 according
without alcohol dependence did not change any of the descriptive fit
to the categorical diagnosis, were moderately mentally healthy.
indices and only changed the latent factor correlation by a single point (i.e.,
Similarly, the most prevalent range of mental health scores was the
–.52).

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COMPLETE STATE MODEL OF HEALTH
545
focusing on the categorical diagnosis of mental health—28% of
of the mental illnesses, suggesting it is not a subclinical form of
languishing and 13% of moderately mentally healthy individuals
any of the four mental disorders. Of the 22.9% of adults who had
(compared with 5% of flourishing adults) had MDE. Flourishing
any of the four mental illnesses, 7.0% were also languishing,
individuals were over 5 times less likely than languishers to have
whereas 15.9% had a pure form of mental illness, meaning this
MDE. Flourishing individuals also were 23 times less likely than
latter group had either moderate mental health or was flourishing.
languishers to have had comorbid mental disorders over the 12-
The functioning axiom predicts that complete mental health is
month period.
the summum bonum of psychosocial functioning, suggesting it is
Table 5 contains the cross-tabulation of whether individuals had
more adaptive than moderate mental health or pure languishing.
any of the mental disorders by the categorical mental health
Findings in Table 5 primarily support the functioning axiom of the
diagnosis to obtain the estimates of the states of complete mental
complete mental health model. Occupational and psychosocial
health. The prevalence of complete mental health was nearly
malfunctioning was lowest, whereas positive functioning was
17.0%, whereas just over 50.0% were moderately mentally
greatest, among adults with complete mental health. Health limi-
healthy. Nearly 10.0% had a form of pure languishing, which is
tations of activities of daily living, any half-day cutback and any
languishing without any of the four mental disorders. Pure lan-
loss of a day of work, and perceived helplessness were least likely
guishers also reported an average of less than one symptom of any
among adults with complete mental health. Moreover, goals, re-
Table 5
Psychosocial Functioning by Categorical Diagnosis of Complete Mental Health (Sample Weighted)
Mental illness
Pure mental
Pure
Moderately
Completely
and languishing
illness
languishing
mentally healthy
mentally healthy
n
214
484
297
1,535
503
Psychosocial functioning
%
7.0
15.9
9.8
50.6
16.6
Health limits—any of nine
Activities of daily living (a lot)
n
73
128
98
349
61
%
34.3
26.4
33.0
22.7
12.1
Any work cutback during past 30 days
n
69
104
32
106
17
%
34.5
22.3
11.3
7.1
3.4
Any lost workday during Past 30 days
n
49
63
22
89
19
%
23.2
13.2
7.7
5.8
3.8
Helplessness
Feel helpless dealing with life’s problems
n
172
161
190
383
27
%
80.4
34.0
64.0
25.4
5.4
Cannot change important things in life
n
99
96
129
381
42
%
46.7
20.2
43.6
25.4
8.5
Goals
Knows what wants out of life
n
52
195
60
599
342
%
24.3
40.7
20.3
39.7
68.0
Finds it helpful to set goal for near future
n
31
163
36
467
267
%
14.5
34.0
12.1
30.8
53.4
Resilience
Changes bad situations for better
n
58
272
73
855
397
%
27.2
56.8
25.0
56.5
79.2
Learns from difficult situations
n
70
284
92
762
346
%
32.7
59.5
31.1
50.5
69.8
Intimacy
Feels really cared for by spouse, partner,
or family
n
157
422
208
1,374
486
%
73.4
87.4
70.0
89.5
96.8
Feels really cared for by a friend
n
58
247
53
729
336
%
27.2
51.8
18.1
48.5
67.3
Note.
For the separate tests of the association of the mental health diagnosis with each psychosocial functioning variable, p
.001 (two-tailed) for all
chi-square tests.

---

546
KEYES
silience, and intimacy were greatest among adults with complete
ever, arguments for or against the study of positive or complete
mental health. Indeed, completely mentally healthy adults gener-
mental health are based on untested assumptions, two of which
ally functioned better than moderately mentally healthy adults; in
were investigated in this article.
turn, moderately mentally healthy adults functioned better than
First, mental health is presumed to be the opposite of mental
adults with pure languishing.
illness; thus, the absence of mental illness equals the presence of
In contrast, occupational and psychosocial malfunctioning was
mental health. Under this assumption, if society can effectively
greatest, whereas positive functioning was lowest, among adults
treat mental illness, then more individuals will become mentally
with a 12-month mental illness on top of languishing. Health
healthy. The current study confirms empirically that mental health
limitations of activities of daily living, any half-day cutback and
and mental illness are not opposite ends of a single continuum;
any loss of an entire day of work, and perceived helplessness were
rather, they constitute distinct but correlated axes that suggest that
greatest among adults with a mental illness as well as languishing.
mental health should be viewed as a complete state.3 Thus, the
Goals, resilience, and intimacy also were lowest among adults who
absence of mental illness does not equal the presence of mental
had a mental illness in addition to languishing, who, as predicted,
health. The structure of mental health as distinct from mental
functioned worse than adults with a pure mental illness.
illness was implied by the introduction of Axis V (Luborsky, 1962)
The contrast in functioning between pure languishing and pure
and the GAF scale to measure Axis V (Endicott, Spitzer, Fleiss, &
mental illnesses generally supports the functioning axiom. In 2 of
Cohen, 1976). However, Axis V remains underused relative to
the 11 indices, individuals with a pure mental illness functioned
other DSM–IV–TR axes, perhaps because the GAF exhibits rela-
worse than individuals with pure languishing. Namely, a higher
tively poor reliability and validity (Goldman, Skodol, & Lave,
proportion of adults with pure mental illness (compared with pure
1992; Roy-Byrne, Dagadakis, Unutzer, & Ries, 1996), and psy-
languishing individuals) had more work cutbacks or lost more days
chologists and psychiatrist rate its usefulness as very low (Frazee,
of work. In 9 of the 11 indices, pure languishing was more
Chicota, Templer, & Arikawa, 2003).
dysfunctional than pure mental illness. For example, one third of
Second, it is commonly assumed that classifying and monitoring
pure languishers, compared with just over one quarter of individ-
the mental health status of individuals, groups, or populations is
uals with pure mental illness, reported any health limitations of
worthless. Individuals free of mental illness are assumed to be
daily activities. Twice as many adults with pure mental illness
homogenous, functioning about the same and markedly better than
(43%) as adults with pure languishing (21%) said that “knowing
mentally ill individuals. However, the diagnosis and measurement
what they want out of life” described them a lot. Twice as many
of mental health— however crude and preliminary some may think
adults with pure mental illness (33%) as adults with pure languish-
of the scheme presented here— has provided some invaluable
ing (15%) said that “it is helpful to set goals for the near future”
information. First, relatively few adults (i.e., about 2 in 10) who
described their situation a lot. Twice as many adults with pure
were free of any of the four 12-month mental disorders could be
mental illness (59%) as adults with pure languishing (26%) said
classified as flourishing or completely mentally healthy. Almost as
that, “When faced with a bad situation, I do what I can to change
many adults were mentally unhealthy (i.e., languishing) as were
it for the better” described them a lot. Nearly 3 times as many
mentally healthy (i.e., flourishing), and most adults were moder-
adults with pure mental illness (54%) as with pure languishing
ately mentally healthy. Second, diagnoses less than flourishing
(18%) said that a “friend that really cares about them” described
were associated with greater levels of dysfunctions in terms of
their situation a lot.
work reductions, health limitations, and psychosocial functioning.
In sum, completely mentally healthy adults exhibited the fewest
Moreover, pure languishing was as dysfunctional (sometimes
health limitations of daily activities, little or no work cutbacks or
more) than pure mental illness (although the pure mental illness
missed workdays, and high levels of psychosocial functioning.
was associated with greater work problems). Mental illness when
Complete mental health was the summum bonum of functioning,
combined with languishing was markedly worse than a pure form
better than the relative absence of mental health—that is, moderate
of mental illness.
mental health and, especially, pure languishing. In turn, languish-
In addition, a recent study confirmed the hypothesis that the
ing was as bad as, and sometimes worse than, the presence of a
complete mental health diagnostic states were independent risk
pure mental illness. Last, complete mental illness—that is, the
factors for cardiovascular disease (CVD; Keyes, 2004). In this
absence of mental health qua languishing and the presence of a
study, I focused on the combination of the categorical diagnosis of
mental disorder—was most dysfunctional, even more dysfunc-
mental health with MDE, because the latter has been shown to be
tional than a pure mental illness, at least as measured by some
a risk factor for heart and arterial diseases. The unadjusted prev-
indicators.
alence of any CVD was 8% among completely mentally healthy
adults, compared with 12% of adults with moderate mental health,
Discussion
12% of adults with pure languishing, and 13% of adults with pure
depression. Among adults who were languishing and had an epi-
Mental illnesses such as MDE are a societal burden and are
sode of major depression, the prevalence of any CVD was 19%. In
projected to become more prevalent and burdensome by the year
multivariate analyses, completely mentally healthy adults had the
2020 (Murray & Lopez, 1996). As such, there is little skepticism
about the societal value of greater support for mental illness
research. Rather than expand the scope of basic and applied
3 The latent factors of mental health and mental illness correlated at –.53,
research to include mental health (Gladis, Gosch, Dishuk, & Crits-
indicating that one quarter of variance between common measures of
Christoph, 1999), treatment and prevention of mental illness ap-
mental illness and mental health (i.e., subjective well-being) is shared
pear at first glance to be more urgent public health issues. How-
variance.

---

COMPLETE STATE MODEL OF HEALTH
547
lowest risk for CVD. Anything less than complete mental health—
resilience has shown that mental health depends on an individual’s
especially for postmenopausal women (for reasons hypothesized
ability to mentally cope with, transform, and find meaningful
and explained in the full study report)—translated into elevated
lessons from the stressors and life’s challenges (Ryff & Singer,
risk for CVD that was comparable with the risk associated with the
2003). Last, a plethora of studies have indicated that interpersonal
known risk factors of diabetes, smoking, and lack of exercise.
relationships that satisfy needs for belongingness and succor are
There are several potential limitations to the current study. First,
instrumental to mental health (Harlow, 1958; Reis & Gable, 2003).
the MIDUS may not provide the most rigorous test of the structural
In sum, mental health has been studied for too long as merely
axiom. Only four mental disorders were measured, and future
the absence of mental illness. It is time to heed the advice of the
research should include a wider assessment of mental disorders to
historic Joint Commission on Mental Illness and Health (see
fully investigate the structural axiom. Second, the subjective well-
Gurin, Veroff, & Feld, 1960; Jahoda, 1958), which recommended
being scales are self-report measures and possibly reflect a bias
the study and promotion of mental health as well as the study and
toward westernized cultures and developed nations. Future re-
treatment of mental illness. Mental health is clearly something
search should include reports on the target’s well-being from
positive, and anything less than flourishing appears to fall short of
others (e.g., experts or family) and investigate whether the struc-
healthy functioning in life.
ture of subjective well-being (i.e., hedonia and eudaimonia), and
dimensions therein, are replicated in other cultures. The sparse
amount of comparative research in this area suggests that the
4 It is unclear who would be the most expert judge of another person’s
structure of subjective well-being is likely to be the same, although
mental health, namely whether it would be a psychiatrist, psychotherapist,
the number and kind of eudaimonic dimensions is likely to vary by
a long-term companion, a teacher or coach, or someone else.
country (see Keyes & Ryff’s, 2003, study).
Third, the proposed diagnostic criteria and the validity of the
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