Validity and reliability of a short questionnaire for assessing the impact of cooking skills interventions

Background: Food skills programmes are widely used as a means to improve confidence in food preparation, the use of basic food skills and food selections amongst low income communities. However, the impact of such interventions are rarely evaluated as a result of a lack of validated assessment tools appropriate for use within this target group. Methods: A two-page questionnaire utilising a closed-question format was designed based on key domains known to be influenced by cooking skills programmes. Content validity was assessed by a panel of public health experts and face validity by individuals, typical of those who may attend cooking skills classes. Internal and repeat reliability were assessed with groups of adults attending community-based classes. The feasibility of using the tool in community settings was also assessed. Results: The draft questionnaire was amended as appropriate subsequent to content and face validity testing. Cronbach's alpha for confidence and knowledge sections was 0.86 and 0.84, respectively, indicating good internal consistency. Spearman correlation coefficients for repeat reliability testing between time 1 and time 2 for each item were in the range 0.46-0.91 (all significant at P < 0.001), indicating that the questionnaire elicited stable responses for repeated use. Feasibility testing highlighted the need for detailed instructions for course tutors on how to distribute and check questionnaires for completion. Conclusions: This tool provides a standardised method of evaluating cooking skills interventions that could be utilised in the development and evaluation of multicentre cooking skills interventions.