Validity and reliability of the Chinese version of the perceived insufficient milk questionnaire

Abstract

Background/Aims This study aimed to translate the perceived insufficient milk questionnaire into the Chinese language, Mandarin, perform cultural adaptation, and evaluate its validity and reliability. Methods The perceived insufficient milk questionnaire was translated using a forward-backward process. An expert panel evaluated content validity with both item and scale content validity indices. Construct validity was assessed by exploratory and confirmatory factor analysis. Internal consistency reliability was evaluated by the Cronbach alpha coefficient. With a 1-week interval, the test-retest reliability was assessed by intraclass correlation coefficient. Results A total of 328 participants were recruited. The item-level content validity index was as high (0.83–1.0), and the scale-level content validity index was 0.92, indicating excellent validity. A single-factor model was verified as acceptable with good fit indices. The internal consistency (Cronbach alpha coefficient=0.943) and test-retest reliability (intraclass correlation coefficient range: 0.870–0.974) were good. Conclusions The Chinese version of the perceived insufficient milk questionnaire had acceptable validity and reliability. It is helpful for healthcare providers to evaluate mother's beliefs about breastmilk quantity and nutritional quality, preventing early cessation of breastfeeding through timely interventions.