Strategies for evaluating self-efficacy and observed success in the practice of yoga postures for therapeutic indications: methods from a yoga intervention for urinary incontinence among middle-aged and older women

BACKGROUND: Most clinical investigations involving yoga lack adequate description of the specific yoga elements, including physical postures. Few studies have measured self-efficacy regarding the performance of yoga postures or assessed observed success in performing postures. METHODS: We developed and piloted several tools to evaluate self-efficacy and observed success in practicing yoga in the context of a randomized feasibility trial of an Iyengar-based yoga intervention for urinary incontinence in ambulatory women ≥50 years. At the end of the 12-week yoga intervention involving twice weekly group yoga classes and once weekly home practice, participants rated their self-efficacy in performing each of the included 15 yoga postures on a 5-point Likert scale. During the 12th week, an expert yoga consultant observed participants and rated their competency in performing postures on a 5-point scale. Participants completed a questionnaire about self-efficacy in adhering to home yoga practice. We examined the distribution of and correlations between scores on the above measures. RESULTS: Among 27 participants (mean age 65 years), the range of means for self-efficacy ratings for individual postures was 3.6 to 4.5. The range of means for observed competency ratings for individual postures was 3.3 to 5.0. Mean self-efficacy rating for confidence in adhering to the assigned once-weekly home yoga practice was 2.8 (range 1 to 5). Posture self-efficacy was inversely correlated with participant age (p = 0.01) and positively correlated with self-reported physical function (p = 0.03) and mobility (p = 0.01). No significant correlations were found between posture self-efficacy scale scores and expert-observed yoga competency ratings or practice adherence self-efficacy scores. CONCLUSIONS: These measures hold promise for advancing yoga research and practice by describing methods to: 1) measure self-efficacy in performing specific yoga postures; 2) use an expert observer to assess participants’ competence in performing yoga postures; and 3) measure self-efficacy in adhering to home practice. These proposed measures can be used to describe specific components of yoga interventions, to assess whether study participants are able to learn to practice physical aspects of yoga and/or maintain this practice over time, as well as to investigate relationships between self-efficacy and competency in performing yoga postures to achieve specific health outcomes. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02342678, January 21, 2015.