Trait Measures. Most research on worry
per se has focused on the construct as a trait, and the "standard"
questionnaire is the 16-item Penn State Worry Questionnaire
Miller, Metzger, & Borkovec, 1990). A sample item is "I am always worrying
about something;" (1 = not at all typical of me; 5 = very
typical of me). Meyer et al. reported strong internal consistency
(alpha = .93) and good test-retest reliability over an 8-10
week period (r = .92). The PSWQ captures the intensity
and controllability of worry (Molina
& Borkovec, 1994), and it discriminates between persons with GAD and
post-traumatic stress disorder. Other researchers show that
the PSWQ has excellent psychometric qualities, whether used
with college students (e.g., Fresco,
Heimberg, Mennin, & Turk, 2002) or outpatients with anxiety disorders
The PSWQ is a "global" worry measure that is free of worry
content; that is, it asks about the extent of worries without
identifying the possible targets of those worriers. Tallis,
Davey, and Bond (1994) developed a content-dependent
worry questionnaire, called "The Worry Domains Questionnaire"
(WDQ). It assesses how much people worry about the domains
of relationships, self-confidence, the future, work, and finances.
Sample items are "I worry that my money will run out," and
"I worry that I'll never achieve my ambitions." Test-retest
over 3 weeks was good for the overall score (r =
.79); not surprisingly, these values were smaller for some
domains for which circumstances may strongly affect worrying
(e.g., test-retest for worry about relationships was r
= .46). The WDQ is strongly correlated with the PSWQ (r
= .67), but the two questionnaires also assess different features
of worrying. The WDQ, for example, may address task-oriented
constructive worrying better than the PSWQ (Davey,
Domain Specific Measures. It is
likely that people may worry about different, specific health
outcomes, and such worries may be independent of or at least
only modestly correlated with trait worry. One of the earlier
scales in the health area was constructed by Caryn Lerman
and her colleagues to study breast cancer (Lerman
et al., 1991).
The "Lerman Breast Cancer Worry Scale" includes
three items, one measuring the frequency of worrying about
"getting breast cancer some day," and two items measuring
the impact of worry on mood and performing daily
activities. In the original study, Lerman et al. averaged
the latter two items separately from the worry frequency item,
a logical approach because the impact items do not ask about
experiencing worry per se.
Partly because of dissatisfaction with the "Lerman Breast
Cancer Worry scale," Champion
et al. (2004) recently created "The Breast
Cancer Fear Scale." The authors especially wished
to capture reports of physiological arousal (e.g., heart rate)
and also subjective aspects of fear. The focus on physiological
responding-even though measured just as self-report-makes
this scale different from others that assess worry. Note,
for example, the lack of items targeting physiological arousal
on the PSWQ. The 8 items on the fear scale provide a scale
range of 8-40, and the items hang together well (alpha = .91).
The scale is reliable over a 2-month interval (r
= .70). It would be interesting to know how closely this scale
correlates with other measures intended to measure worry per
Because worry involves negative thoughts, some researchers
have used the intrusive thoughts subscale from the Revised
Impact of Events Scale (RIES; Horowitz,
Wilner, & Alverez, 1979) to measure the concept.
The intrusive thoughts subscale has strong
internal consistency (e.g., alpha = .86) and good test-retest
reliability (r = .87 for one week; see Sundin
& Horowitz, 2002). The RIES was originally constructed
as a measure of stress reactions following traumatic events,
and it has been used in that manner in the cancer arena as
well (e.g., Vickberg,
Bovbjerg, DuHamel, Currie, & Redd, 2000). However, Wells
and Papageorgiou (1995) proposed that,
to the extent that worry interferes with emotional processing,
worry itself could lead to the subsequent production of intrusions.
In this model, then, worry actually creates higher levels
of intrusive thoughts, a phenomenon that has been demonstrated
by Borkovec and colleagues (York,
Borkovec, Vasey, & Stern, 1987). These data suggest that intrusive
thoughts are a product of different kinds of worrying
rather than another measure of worry. The intrusions subscale
includes seven items, and it can be reworded to measure how
often during the previous week the respondent experienced
intrusive thoughts about the consequences of different health
outcomes (e.g., one could use lung cancer in the items, producing
statements such as, "Pictures about lung cancer popped into
my mind;" "Any reminder brought back feelings about lung cancer;"
0 = not at all; 1 = rarely; 3 = sometimes; 5 = often).
Finally, it is possible to construct very brief scales that
will measure worry about a particular domain reliably. In
our work, we have used two items that ask directly about the
degree of worry (e.g., "How worried are you about developing
a smoking-related medical condition?", and "How much does
thinking about a smoking-related medical condition bother
you?" 0 = not at all; 4 = extremely). In a study of college-student
smokers, these two items were inter-correlated (alpha = .87),
and the average score correlated modestly with the PSWQ (r
= .31), intrusive thoughts (r = .29) and the motivation
of these smokers to quit (r = .29; McCaul
et al., 2005).
and Brosschot (2003) recently took a similar approach, creating
a worry "scale" to study smoking. Their 4 items (alpha = .95)
focused on the intensity of worry [e.g., "I worry about my
health because of my smoking"-not at all (1) to very much
(7)]. Smokers in their prospective study who worried more
about the health effects of smoking also reported higher quitting
Summary.. How should one measure worry? The PSWQ makes perfect sense if the researcher is interested in a
relatively brief, well documented trait-worry scale that lends insight into the general intensity and controllability of everyday worrying. The WDQ also makes sense as
a general measure-in this case, one assessing worrying about five everyday domains. Measuring worry about particular health events is more up in the air, and
none of the existing scales is perfect. Lerman's scale includes both frequency but also "impact" items, Champion's fear scale asks about fear
(rather than worry; see below) and also includes physiological arousal, which is not a part of the worry construct as envisioned by most theorists.
Intrusive thoughts are related to worry but may not be the same thing, and the two-item scales we have used address worry intensity (how much do you
worry?) but not frequency ("how often do you worry"?). The final scale included in the Appendix is one that we created to illustrate both dimensions of worry.
It has not been tested, but it borrows from the other scales and could be a reasonable measure for researchers to try. Note carefully, however, that we
do not have psychometric data for it as yet, and we do not know whether worry frequency and intensity should necessarily be combined or whether they should be considered as
separate influences on health behaviors. More research along these lines would be welcomed.