• Dr. Tilak Kumar B S

Abstract This cross-sectional study investigated sleep quality as a significant predictor of cognitive performance among university students (N=150). Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), while cognitive performance was measured through validated standardized tasks evaluating attention, working memory, processing speed, and executive function. Descriptive statistics revealed that 30.7% of students experienced poor sleep quality, while 50.7% exhibited fair sleep quality. Spearman's rank-order correlation analysis demonstrated significant negative associations between PSQI scores and all cognitive domains (r = -0.521 to -0.687, p < 0.001). Mann-Whitney U tests confirmed significant differences in cognitive performance between good and poor sleep groups (all p < 0.001). Multiple linear regression analysis (R² = 0.587, adjusted R² = 0.567) confirmed sleep quality as an independent predictor of cognitive outcomes after adjusting for demographic variables (age, gender, year of study) and lifestyle factors (exercise frequency, caffeine consumption). Effect size analysis revealed large practical significance for the sleep-cognition relationship (Cohen's d = 1.72-2.14). The intervention group (n=42) demonstrated clinically meaningful improvements in PSQI scores (10.2 ± 2.1 to 6.8 ± 1.9, p < 0.001) and cognitive performance following targeted sleep hygiene and stress management interventions. The findings underscore the critical importance of sleep quality in supporting cognitive functions essential for academic achievement and suggest the necessity for targeted, evidence-based interventions to enhance student well-being. Limitations included the cross-sectional design for the observational phase and potential recall bias in self-reported measures. The study recommends future longitudinal investigations with objective sleep measurement methods (actigraphy, polysomnography) to establish causality and evaluate long-term intervention efficacy.

Keywords: sleep quality, cognitive performance, university students, Pittsburgh Sleep Quality Index, statistical analysis, cross-sectional study, academic achievement, effect size, intervention outcomes

"Sleep Quality as a Predictor of Cognitive Performance in University Students: A Cross-Sectional Study ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.13, Issue 1, page no.a470-a485, January-2026, Available :http://www.jetir.org/papers/JETIR2601058.pdf

"Sleep Quality as a Predictor of Cognitive Performance in University Students: A Cross-Sectional Study ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.13, Issue 1, page no. ppa470-a485, January-2026, Available at : http://www.jetir.org/papers/JETIR2601058.pdf