Psychometric of Water Intake Questionnaire in Patients with Kidney Stones: Investigation of Socio-Cognitive Determinants

Developing a valid and reliable questionnaire is an essential step in field studies. The present study aimed to evaluate the psychometric properties of the socio-cognitive determinants of water intake questionnaire behaviors among patients with kidney stones in the west of Iran.

Construct items were elicited from interviewing patients with kidney stones, experts, and socio-cognitive items pool-related similar questionnaires. Internal consistency, as well as face, content, and construct validity, were evaluated. Data were analyzed in SPSS (version 20.0). Based on Eigenvalues of ≥ 1.00 and factor loadings of ≥ 0.40, five determinants were extracted.

The calculated Kaiser-Meyer-Olkin (KMO) value was 0.697. The socio-cognitive determinants of water intake questionnaires were found to have acceptable internal consistency (Cronbach alpha of determinants between 0.65-0.85), and the theoretical assumptions for face, content, and construct validities were confirmed. The Intra-class Correlation Coefficient (ICC) of socio-cognitive determinants was high (ICC between 0.810 - 0.911). In general, the five studied socio-cognitive determinants explained 73.83% of the variance in the proposed model.

The socio-cognitive determinants of the water intake questionnaire were revealed to have an acceptable psychometric evaluation. The questionnaire could be used to predict or explain water intake behavior in order to develop programs to increase water intake behavior among patients with kidney stones.