Table 1.

Defined PICO-based search strategy, and listed exclusion criteria

Population	Patients with Alzheimer’s disease or undefined dementia
Intervention	Pain treatment defined as a pharmacological intervention in which the medications employed are named and dosages listed
Comparison	All studies using standard care as usual group comparison or other valid comparison alternatives before/after comparison
Outcome	Only studies employing quantitative measures and analyses were included. Outcomes included assessment of pain (yes/no or pain intensity) as well as assessment of pain-related behavior, e.g., neuropsychiatric symptoms
Exclusion criteria	(1) Qualitative studies, (2) single case studies and those including less than ten patients, (3) methodology papers, (4) study protocols, (5) animal studies, (6) non-pharmacological studies, (7) deep brain stimulation and other experimental studies, and (8) conference abstracts. On the basis of these exclusion criteria, the authors screened potential manuscripts at the abstract level and applied the review protocol of described inclusion and exclusion criteria on selected full texts; we also searched through the reference lists of the full-text publications

PICO problem/population, intervention, comparison and outcomes