How strong is the evidence for Consistent Sleep Schedule?

Evidence specific to fixed bed and wake times draws mainly on a randomized sleep-education trial in college students and observational research on circadian misalignment's effects on cortisol and inflammation, alongside broader reviews of circadian sleep-wake phase disorders. That evidence is currently rated emerging (36/100), built on 5 published studies, including 1 randomized controlled trial -- still too little to draw firm conclusions from.