Development and validation of the Patient's Health Belief Questionnaire on Psychiatric Treatment.

BACKGROUND

Our previous studies with regard to adherence to psychiatric medications measured pharmacophobia, psychological reactance, and locus of control using a 42-item questionnaire requiring ~1.5 hours for completion. This study aims to develop the Patient's Health Belief Questionnaire on Psychiatric Treatment, a 17-item inventory which requires only 15 minutes to complete.

METHODS

Our new questionnaire with five subscales was based on 17 items from three previously validated scales (on pharmacophobia, psychological reactance, and locus of control). In 588 consecutive Spanish psychiatric outpatients taking 1,114 psychiatric medications, we studied the responses to the questionnaire; to validate it, medication adherence was assessed by the Sidorkiewicz tool.

RESULTS

Validation of the construct was addressed by performing two exploratory factor analyses independent of each other (one for the eight-item section measuring the attitudes of patients toward psychotropic drugs and one for the nine-item section measuring perceived health locus of control [HLOC]), which led to five subscales that were called Positive and Negative Aspects of Medications, Doctor-HLOC, Internal-HLOC, and Psychological Reactance. The five subscales showed better internal consistency when corrected by number of items than the original 17-item scale. Logistic regression models of the continuous scores, dichotomized subscales, and Chi-squared Automatic Interaction Detector (CHAID) analysis indicated that all five subscales help in predicting adequate adherence, although the various subscales behave differently in different analyses.

CONCLUSION

Future studies need to verify and further extend the preliminary findings of this study that the questionnaire may have construct and predictive validity.