METHODS: A total of 62 participants aged between 13 and 17y were involved. A self-administered questionnaires containing 12 items was used to evaluate the smartphone usage patterns. This was followed by an eye examination, involving a battery of accommodation and convergence assessments before and after the smartphone use. The data analysis comprised descriptive statistics, paired t-test, and correlation coefficients.
RESULTS: The use of smartphones is at a high level and at an optimal distance daily, with more than 6h a day watching video films, games, and completing school projects. Majority of the participants not reported eye strain factors and eye prescription changes with the use of digital devices. The use of a smartphone continuously for 30min was found to significantly decrease amplitude of accommodation, accommodative facility, and positive relative accommodation (P<0.001). Meanwhile, the lag of accommodation parameters and negative relative accommodation increased with the use of smartphones significantly (P<0.001). The near point of convergence (NPC) and distance and near negative fusional vergence decreased significantly (P<0.001). The NPC parameter was found to have a weak negative association with the frequency of smartphone use (R=-0.276, P<0.05).
CONCLUSION: Frequent and continuous use of smartphones have increased visual stress and resulted in weakness of accommodation and vergence functions. Therefore, frequent break is mandatory when using a smartphone and appropriate visual hygiene, the 20-20-20 rule (every 20min, view something 20 feet away for 20s) are required during smartphone use to maintain visual function.
METHODS: This study was conducted among patients diagnosed with AMD in Kuala Lumpur. The generation of the instrument included four phases which included item and domains development, content, face validity and exploratory factor analysis. Content validity and modified Kappa was used for validation of knowledge domain. Exploratory factor analysis was used for validation of both attitude and practice domains. Face validity was conducted in 12 patients, content validity was ascertained in 120 patients and test-retest reliability was determined in 39 patients with AMD.
RESULTS: Content validity index (CVI) and modified kappa showed excellent values for most items in the knowledge domain with CVI for item (I-CVI) values between 0.78-1.0 and Kappa values of >0.74. The Kaiser-Meyer-Olkin (KMO) sampling adequacy showed acceptable scores of 0.70 and 0.75 for both attitude and practice domains respectively and Bartlett's Test of sphericity were significant (χ2 =0.00, P<0.001). Factor analysis resulted in five factors with thirty items for attitude domain and four factors with twenty items for practice domain. The Cronbach's alpha showed acceptable values for all items in knowledge, attitude and practice domain with values >0.70 and good test-retest reliability. The final version of the questionnaire consisted of 93 items from four sections consisting of demographic details, knowledge, attitude and practice.
CONCLUSION: The findings of this validation and reliability study show that the developed questionnaire has a satisfactory psychometric property for measuring KAP of patients diagnosed with AMD undergoing intravitreal injection treatment.