Table 1 Overview of CSF melatonin levels in AD as compared to controls. ↓ means a significant reduction in CSF melatonin in AD when compared to controls. ✖ means no data comparing CSF melatonin levels between AD and controls were available. A black star ★ was attributed per NOS criterium per category (selection, comparability, exposure) met. Stars were kept white ☆ if the NOS criterium in the corresponding category was not met