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BackgroundMost eye problems among children can be detected and treated at an early age to reduce the prevalence of visual impairment. Understanding the knowledge, attitude, and practice (KAP) among parents about common children’s eye problems is fundamental to encourage parents to seek early eye care services for their children. This study aims to develop a Parental Knowledge, Attitude, and Practice in Eye Problem among Children Questionnaire (PEPC-KAPQ) and evaluate its psychometric properties.MethodsThis study involved developing a questionnaire and was conducted in Kuala Lumpur, Malaysia from July 2021 until June 2022. The questionnaire was developed based on a literature review and expert consultation. The first phase includes a systematic literature review to generate the items for the questionnaire. A group of five panels was then invited to perform content validity for the questionnaire. Face validity was conducted among ten parents to get feedback for the questionnaire. Construct validity and reliability of the questionnaire were measured by which the questionnaire was administered to a total of 134 parents and 64 parents for reliability test.ResultThe final PEPC-KAPQ consists of four main sections: demographic, knowledge, attitude, and practice with 52 items. The content validity index was 0.85 for all domains of KAP. Modified kappa showed excellent value for most items for all domains. The Kaiser-Meyer-Olkin sampling adequacy showed acceptable scores of 0.84, and Bartlett’s Test of Sphericity was significant (x2 = 3172.09, pα coefficient of domain attitude and practice were 0.92 and 0.88, respectively and the intraclass correlation of domain attitude and practice were 0.93 and 0.94 respectively. Bland and Altman’s plots show that majority of the data fell within the limits of agreement.ConclusionThe findings of this validation and reliability study show that the developed questionnaire has a satisfactory psychometric property for measuring the KAP of parents regarding eye problems among children.