PSQI Sleep Quality Calculator

The PSQI sleep-quality calculator accepts seven component ratings, each coded from 0 to 3, matching the Pittsburgh Sleep Quality Index that Daniel Buysse and colleagues published in 1989 as a self-rated questionnaire assessing sleep quality over the past month. It rounds each entry to a whole number, limits it to that range, and adds the components to form a Global PSQI Score from 0 to 21. Larger component codes represent worse sleep conditions in every field, including subjective quality, latency, duration, efficiency, disturbances, medication use, and daytime dysfunction. Since the global result is a simple sum, all seven components have equal one-point influence. The Poor Sleeper output is binary. It remains 0 for global scores through 5 and becomes 1 only when the sum is greater than 5.

Worst Component reports the position of the largest component: 1 for quality through 7 for daytime dysfunction. Ties are resolved by input order because the search changes its selection only when it encounters a strictly larger score. For example, equal maximum ratings for quality and latency leave quality, component 1, selected. This implementation starts from already-derived component codes rather than the full questionnaire responses used to derive them. It does not calculate actual sleep efficiency from bed and sleep times, combine disturbance sub-items, or assess causes such as breathing disorders, pain, schedules, substances, mood, or medication effects. The result is therefore a compact arithmetic summary of the seven values entered, not a diagnosis of insomnia or another sleep disorder.