A new approach to the measurement of ophidiophobia

Person. indioid. Difl

Vol. 16, No. 3. pp. 505-508,

1994 Ltd Printed in Great Britain. All rights reserved 019l-8869194 $6.00 + 0.00

Copyright <<;1994 Elsevier Smnce

Pergamon

A new approach to the measurement DOUGLAS

M.

of ophidiophohia

KLIEGER

Department of Psychology, Villanova University, Villanova, PA 19085-1699,

U.S.A.

(Received 25 June 1993) and physiological Summary-Current measurement of emotion often produces cognitive, behavioral, measures that disagree. Rather than accept the situation as unresolvable the study sought to improve the quality of measurement by removing much of the ambiguity inherent in typical measures of fear. Sixty five (sample 1) and 173 (sample 2) subjects were given an automated version of the Snake Anxiety Questionnaire and an extensive series of follow-up questions ending with a behavioral approach test. Follow-ups were asked contingent on the degree of ambiguity and the subject’s response using branching logic. This system has been termed “Initial Response Verification”. The process was successful in reducing the number of false-positive (defined as high cognitive-low behavioral fear) identifications from 100 of 228 to 14 of 228, which was significant at the P < 0.001 level. These reductions were distinctly different from those of a simple linear transform and were unique to each individual. In sum, behavioral and cognitive measures need not disagree when ambiguity is removed.

In the measurement of fear it is an unfortunate truism that cognitive, behavioral, and physiological measurements of emotion seldom agree (Himadi, Boice & Barlow, 1985). This difficulty has come to be known as desynchrony and has most recently been reviewed by Turpin (1991). The general conclusion in this review is one of confusion. conflicting results and unfulfilled promise. One partial solution is to accept the independence of these response modalities and refrain from making cross-modality & Rachman, 1974; Rachman & Hodgson, 1974). Such acceptance may be premature if the ~ I Ioredictions (Hodeson measurement of any of these modalities is significantly flawed. In the area of ophidiophobia (snake fear) there is increasing evidence of considerable mismeasurement. In the specific case of analog research with college students Klieger (1987) demonstrated that the Snake Anxiety Questionnaire (SNAQ; Klorman, Weerts, Hastings, Melamed & Lang, 1974) seriously overestimates the number of snake fearful college students. More recently, Klieger and Franklin (1993) have demonstrated that the ubiquitous Fear Survey Schedule (FSS; Wolpe & Lang, 1977) similarly overestimates the number of snake fearful college students. These overestimations are a prime example of disagreement between cognitive measures (the SNAQ and FSS) and a behavioral measure, in this case a behavioral approach test or BAT. One solution to these difficulties would be to generate a long list of potential items and apply the traditional empirical approach. However, this is the very style of the SNAQ. In this paper I propose that much of the disagreement among modalities in the measurement of emotion will disappear when the ambiguities inherent in the current measures are removed. “I would feel uncomfortable wearing a snakeskin belt” is a SNAQ item with inherent ambiguity. The individual answering True may be doing so in response to one or more of the following: rational fear associated with a conditioning experience, irrational fear, moral objections to wearing animal skins, or feelings of revulsion and disgust not related to fear. A simple and direct method to resolve these ambiguities would be to simply ask the S about moral objections, revulsion, etc. Elimination of ambiguity through perceptive follow-up questions has not, heretofore, been a practical option, Now, with wide availability of computers and programming software it is possible to present questions and follow-up questions conditioned on the S’s response in a logical and efficient way. The research presented here tests a method for removing item ambiguity and demonstrates the significant changes that result. I have named this process “Initial Response Verification”.

METHOD Study I The SNAQ (Klorman et al., 1974) was implemented within the FLEXTEST system (Klieger. 1990) which provided the opportunity to ask unlimited follow-up questions with unrestricted branching logic, A set of 77 follow-up questions was created from the perspective of rational test construction. The content of these questions was designed to reduce ambiguities arising from factors such as disgust and revulsion, inexperience and lack of information. like or dislike of elements unrelated to snakes, disinterest in the proposed behavior without respect to snakes. and moral/ethical objections. Subjects The S sample consisted of 54 female and 11 male college students whose average age was 19.5 years. All were volunteers who received class credit for their participation. Recruitment was via a departmental “subject” bulletin board request whose title made no mention of snakes, Informed consent and debriefing principles were observed throughout. Three Ss were excluded because of power failures, fire alarms and the like. 505

506

NOTES AND

SHORTER

COMMUNICATIONS

Muterids

The 30.item SNAQ (Klorman PI al.. 1974) and the 77 follow-up questions were implemented with the FLEXTEST system (Klieger, 1990) on an Apple Ilgs computer. * The fear stimulus for the BAT was a 45cm Canadian garter snake (non-poisonous) housed in a 10 gallon glass terrarium with a wire screen top. A separate terrarium was maintained exclusively for the BAT test so that the testing conditions might be maintained at a high level of cleanliness.

After initial greeting, all Ss were given informed consent/instruction procedures for the questionnaire portion of the study. Upon completion, a separate consent/instruction form describing the BAT procedure was administered. Ss who objected to the BAT were simply given the highest BAT score and immediately debriefed. Thus, the degree of approach was under S control. As recommended by Bernstein and Paul (1971) and Bernstein (1974) high demand was used to encourage Ss to make a strong approach elfort. The BAT details are available in Klieger (1987) and were in essence a 14-step graded approach ending with the S touching the outside of the terrarium. The BAT took place in a separate room adjacent to the room for the questionnaire part of the study. In sum, from the Ss’ point of view the sequence of events was: (1) reading the consent/instructions for the computer administration of the SNAQ and follow-up questions, (2) completion of the original SNAQ followed immediately by the follow-up questions, (3) reading the consent/instructions for the BAT and completion of the BAT, (4) debriefing.

StudyII The second study was conceived of as a cross-validation of the first and was run during the following semester. All procedures were identical except for the experimenter: both were female however. The Ss were 91 female and 82 male students from the same university and their average age was 19.1 years, Six Ss were excluded because of power failures, fire alarms and the like. RESULTS Because Study II was conducted as an unmodified cross-validation of Study I the results are presented together. Genders are presented separately throughout the results because of the normative differences (see. Klorman et ~1.. 1974 and Klieger. 1987). Table 1 presents the descriptive statistics for each sample and it is clear that the two are the same. Only 1 of the 65 Ss exhibited any degree of behavioral fear in Study I and 8 of 173 in Study II when defined as a BAT score > 1. All other 5’s were able to touch the terrarium successfully. On a percentage basis, this 3.4% fear rate approximates Klieger’s 1987 finding of 2% and Klorman et 01,‘s (1974) finding of 2 to 3%. If a false-positive S is defined as one who scores above the 75 percentile on a normative basis and yet has a low BAT score, then fully 62% of the women in Study I and 53% in Study II qualify. Thus, the current data agree with Klieger’s (1987) finding that the SNAQ produces large numbers of false-positives. To determine if adding follow-up questions to the SNAQ would reduce the number of false-positives a correction score was computed. This score was calculated by summing all responses in the keyed direction. The key was determined on a strictly logical basis, i.e. it is completely reasonable to discount a S’s original response if, on the basis of follow-up questions, it is clear that the S’s view of the question was different from the view that determined the original keying. Thus, when a S who said True to the question “1 would feel uncomfortable wearing a snakeskin belt” also states that they would feel uncomfortable because they morally object to wearing animal skins of any kind, the original True response must be discounted. The reader should keep in mind that a True response cannot be discounted until all original item ambiguities are resolved. From the results of the follow-up questions, a new SNAQ score was calculated by subtracting the correction score from the unadjusted SNAQ. The effect of this discounting process is summarized in Table 2. Corrections were truncated at zero when the amount of correction exceeded the SNAQ score. Thus the number of false-positive women in Study I was 33 of 54 before correction and 4 of 54 after correction. To assess these changes the test for the significance of a single proportion was applied (Brunning & Kintz, 1968. p. 197). Thus the proportion of false-positives from the new scoring procedure was compared to the number of false-positives from the standard scoring procedure. and ; = -2.03 (P < 0.05) for men. The test of proportion for women in Study I produced a z = -8.22 (P < 0.0000) Study II produced a ; = -8.55 (P < 0.0000) for women and 2 = -3.93 (P < 0.01) for men. Thus all four tests exceeded the chosen alpha criterion of 0.05. The correlation between the original SNAQ and the NEWSNAQ is r = 0.54 (P i 0.001) which is as expected. To determine if the adjusted scoring was substantively different from a simple linear transformation, the average correction increased the number of ( ~ 6 for women. ~ 3 for men) was subtracted from the original scores. This transformation

Table

I. SNAQ. derived scores and BAT descriptive

SNAQ score

Sample I W0men MelI

Sample II W0meil MeIl

Correction

statistics

NEWSNAQ

BAT

Mean

SD

Mean

SD

Mean

SD

Mean

SD

x

IO Y 5.1

5.9 2.1

6.8 2.9

3.5 2.2

4.1 2.2

3.6 1.3

1.2 I.0

I.5 0.0

54 II

IO.6 4.7

5.x 4. I

6.4 2.1

3.4 2.5

4.2 2.0

3.3 2.35

1.7 1.0

7.7 00

YI 82

These values include fearful and non-fearful

Ss.

*The general logic and programming structures for the FLEXTEST system are available in Klieger (1990). Copies of the programs in Apple (but not Macintosh) and IBM format are available from the author. The 77 follow-up questions are also available from the author.

NOTES AND SHORTER

Table

2. Frequency

of

SNAQ scores and adjusted scores classified by gender and auartile

Original SNAQ

Adjusted SNAQ

Quartiles

Quartile

4

Quartiles 1.233

Quartile 4

20 8

33 (62.3%) 3 (27.3%)

49 II

4 (7.5%) 0 (0.0%)

39 62

45 (53.6%) 19 (23.5%)

7x 77

6 (7.1%) 4 (4.9%)

58 70

78 (57.4%) 22 (23.9%)

126 88

IO (7.4%) 4 (4.3%)

1J.3

Sample I Women MelI Sample II W0men MelI Combined WOlIEIl MelI

507

COMMUNICATIONS

Ss with measurable behavioral fear are not included.

false-positives considerably. In Study I the number of women increased from 4 to I1 (from 7.5 to 20.8%) while the men remained unchanged. In Study II the number of women increased from 6 to 12 (from 7.1 to 14.3%) while the men increased from 4 to 13 (from 4.9 to 16.0%). Descriptively, it is clear that the discounting process is distinctly different from a simple linear transform. A statistical comparison of current results to Klieger’s (1987) norms was not done because of the substantial agreement between studies. Correlations between the standard and the new scoring procedures for false-positive Ss were not done because of the individual adjustment nature of the process, i.e. the correlations would be uninterpretable.

DISCUSSION It is clear from these results that the process of using the branching logic abilities of the FLEXTEST system when coupled with a set of follow-up questions designed to disambiguate a specific questionnaire was quite successful. Overall the process reduced the number of false-positive Ss from 100 to 14. With two samples the process of Initial Response Verification can be considered strongly cross-validated. To some readers the labor intensive process of writing good follow-up questions for the sole purpose of reducing ambiguities in the original question might constitute misplaced effort (effort better directed toward rewriting the original questions). However, many worthwhile questions require more information from the S than can be gathered in one item. For example, the SNAQ item “I think that I’m no more afraid of snakes than the average person” demands that the Ss concept of average fear be determined. A rewrite of the original item could logically contain only the author’s or some empirically determined notion of average fear. The follow-up process allows the researcher to ask what the S considers average which then places the focus where it should be on the S. Changing the definition of false-positive Ss from that used here would alter the specific numbers but not their meaning. Examination of the distributions suggests that changes of 5 to 10 percentage points would not alter the results. Setting the criteria unusually high (say the 95 percentile) risks eliminating Ss with confirmable behavioral fear. These results confer directly with Hodgson and Rachman’s (1974) contention that fear and avoidance of fear objects do not correspond in ophidiophobia. Somehow, fear of snakes is different. The current results suggest that much of this lack of correspondence, or desynchrony, may be attributed to inadequate self-report measures. Unfortunately, this means that studies using the SNAQ and similar measures have contained hidden measurement problems. As a consequence, evaluations of treatments, particularly those using analog procedures, and studies examining the nature of ophidiophobia have presented misleading conclusions and are in need of reevaluation. This call for reevaluation does not apply to studies where initial fear reports were confirmed by clinical, behavioral, or physiological means. Studies lacking confirmation are not rare; the interested reader should see Klieger and Gallagher (1993). One clear implication of this research is that the many epidemiological studies of fear may suffer from similar measurement error. Further research may reveal that interviewing respondents about fear without initial response verification is much the same as administering the SNAQ without follow-up. It is important to view these results and conclusions with some degree of caution. The demonstration that some desynchrony is due to insufficient measurement of the cognitive component, does not imply that the phenomenon is not real. It also does not suggest that assessment of the three components will not be useful from a treatment point of view. The current results do not speak to desynchrony effects involving physiological measures nor do they suggest that initial response verification will succeed with complex phobias. There are several points about the FLEXTEST follow-up question process that have yet to be determined. First, the logic and content of the follow-up questions may require further development. For example, a brief item review revealed several questions that were never asked. Second, though work is underway to extend the system to other measures of fear, it is an open question whether sensible follow-up questions (items) can be created in content areas where S knowledge is low or confused, i.e. depression, Third, some degree of caution is called for because the psychometric effects of the response verification process are unknown. Work is underway to examine the possibility that follow-up questions will lower test-retest correlations by encouraging Ss to reevaluate their responses to ophidiophobia questions. Intriguingly, this suggests that upon a second retest reliabilities should stabilize. In summary, this study has demonstrated that it is possible to reduce the ambiguities in ordinary fear items and thus significantly reduce the number of false-positive Ss. This in turn strongly suggests that there need not be disagreement between cognitive and behavioral measures of fear.

508

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