Further validation of the 5-item Perceived Efficacy in Patient–Physician Interactions (PEPPI-5) scale in patients with osteoarthritis

Abstract

Objective

To examine the structural validity, internal consistency, test–retest reliability, and construct validity of the 5-item Perceived Efficacy in Patient–Physician Interactions (PEPPI-5) scale in patients with osteoarthritis (OA).

Methods

A cross-sectional sample of 224 outpatients with OA completed a survey containing the Dutch PEPPI-5 and other standardized measures assessing perceived health-management skills, general self-efficacy, social support, and health-related quality of life. A subsample of 100 patients completed the PEPPI-5 again approximately 3 weeks later.

Results

Confirmatory factor analysis demonstrated good fit for a unidimensional model of the PEPPI-5. Additionally, the scale showed high internal consistency (α = 0.92) and fair test–retest reliability (ICC = 0.68). As hypothesized, the PEPPI-5 was strongly correlated with perceived health-management skills, moderately with social support and psychosocial aspects of health, and not with physical aspects of health. Contrary to expectations, however, it was not correlated with general self-efficacy.

Conclusion

The Dutch PEPPI-5 demonstrated adequate validity and reliability in patients with OA.

Practice implications

The PEPPI-5 is a brief and appropriate tool for measuring self-efficacy of patients with OA to interact with their physicians. Additional research into its sensitivity to change is needed before it can be confidently recommended as an outcome measure in intervention studies.

Introduction

Good patient–physician interaction has been shown to be associated with a wide range of improved healthcare outcomes, including better adherence to treatment, improved satisfaction with care, and improved health outcomes [1], [2], [3], [4], [5], [6], although the exact pattern of associations is not always consistent [7]. Whereas considerable research has examined the effects of physicians’ patient-centered communication skills and styles, less attention has been given to patients’ self-efficacy and skills in interacting with physicians. Effective patient–physician interaction is also likely to be dependent on the assertiveness of patients themselves, i.e., their confidence in their ability to interact with physicians. Indeed, educational interventions aimed at empowering patients to address their own needs, have shown to be successful in increasing patients’ sense of control and preference for a more active role [8], [9], [10]. Consequently, improving patients’ self-efficacy in communicating with their physicians is an important component of most current self-management programs [11], [12].

Although a wide range of disease-related self-efficacy scales are available [13], few validated measures specifically address patients’ self-efficacy to interact with physicians [14]. The widely used self-efficacy measures developed by Lorig et al. [15] contain a 3-item subscale assessing patients’ confidence in communicating with their doctor. However, its items are somewhat limited in scope and no information is available about the content and construct validity of the subscale. Additionally, two general stand-alone measures have been developed and validated for measuring patient communication self-efficacy: the Ask, Understand, Remember, Assessment (AURA) scale [14] and the Perceived Efficacy in Patient–Physician Interactions (PEPPI) questionnaire [16]. The just recently published AURA is a brief 4-item scale measuring patients’ self-efficacy to obtain, understand, and recall information in a clinical setting. Although the scale showed promising internal consistency and was moderately correlated with Lorig's chronic disease self-management self-efficacy scale in patients with hypertension, its psychometric qualities in other populations and association with actual clinical outcomes still need to be confirmed [14]. The slightly more elaborate PEPPI has been in use for somewhat longer and is the focus of the present study.

The PEPPI was developed to measure older patients’ self-efficacy in both obtaining medical information and attention to their chief health concern from a physician [16]. The original version of the PEPPI consisted of 10 items and demonstrated excellent structural validity, internal consistency (α = 0.91), and adequate convergent and discriminant construct validity in a sample of 163 community-dwelling older adults with a mean age of 77 years. Additionally, a 5-item short form was developed that consisted of those items that demonstrated the most variability while maintaining adequate internal consistency and construct validity [16]. The PEPPI-5 performed nearly as well as the full 10-item version, with high internal consistency (α = 0.83) and nearly identical convergent and discriminant validity.

Convergent and discriminant validity of the PEPPI-5 in the original study [16] was established by demonstrating that the scale had a strong positive correlation with patient satisfaction with communication and interpersonal manner of care. Additionally, there was a weak negative correlation with avoidant coping and a weak positive association with active coping. Another study using the scale in low-income patients with prostate cancer found that patients with low PEPPI-5 scores had significantly lower scores on emotional well-being, symptom distress, role limitations-emotional, and social functioning and slightly lower scores on physical functioning [17].

To date, however, the structural validity and convergent and discriminant validity of the PEPPI-5 have not yet been thoroughly examined in clinical and more age-diverse samples. Moreover, the test–retest reliability of the scale has not yet been established. Therefore, the aim of the current study was to examine the structural validity, internal consistency, test–retest reliability, and convergent and discriminant validity of the Dutch PEPPI-5 in a clinical sample of outpatients with OA.