2.3.2. Mediators (M)
Self-efficacy for diet was measured using a 20-item instrument (internal consistencies = 0.70–0.88) on 5 subscales (i.e., negative emotions, availability, social pressure, physical discomfort, and positive activities) for high-calorie foods by Clark et al. [Social support for diet was measured using a validated (r = 0.55–0.86 and internal consistencies = 0.61–0.91) 4-item instrument on 3 subscales (i.e., participation, involvement, and encouragement) by Sallis et al. [The frequency of encountering barriers to following a low-calorie, healthful diet was assessed using a 10-item questionnaire with anchors ranging from 1 = Never to 5 = Every day [