What does an increase in sleep efficiency generally indicate?

An increase in sleep efficiency is a positive indicator of sleep quality. Sleep efficiency refers to the ratio of time spent asleep to the total time spent in bed. A higher percentage suggests that an individual is spending a greater proportion of their time in bed actually sleeping rather than lying awake. This improvement typically reflects better sleep quality, meaning that the individual is falling asleep more quickly and experiencing fewer disruptions during the night. As a result, their overall restorative sleep is enhanced, contributing to various physical and mental health benefits.

The other choices do not align with the concept of sleep efficiency. For instance, a higher percentage of sleep disturbances would indicate that an individual is having more trouble maintaining sleep, not an improvement. A decreased need for sleep is typically not related to sleep efficiency itself, as it encompasses the overall amount of sleep required rather than the effectiveness of that sleep. Worsening sleep habits would conversely suggest a decrease in sleep efficiency, as they would typically lead to more awakenings and lighter sleep.