Eligibility Criteria	Inclusion Criteria	Exclusion Criteria
Population (P)	PLWH who were evaluated for the detection of HHV-6	Immunocompromised patients for reasons other than HIV infection and solely pediatric populations
Exposure (E)	The exposure of interest was the detection of HHV-6 in blood using molecular methods	Other human herpesviruses (HHVs)
Comparison (C)	Given that our objective was to quantify the prevalence, a direct comparison component does not apply within our study’s framework	-
Outcome (O)	The primary outcome was the detection of HHV-6 in blood using molecular methods. Additionally, we aimed to identify risk factors	Studies assessing seropositivity using other diagnostic methods (e.g., serological methods such as ELISA), other body fluids (e.g., saliva, solely serum) [12,13,14], or different body tissues
Study Type (S)	Observational studies including cohort, case–control, and cross-sectional studies	Case reports, case series with ≤20 participants, review articles, systematic reviews, meta-analysis, interventional studies including randomized clinical trials and non-randomized clinical trials, comparative studies, animal studies, letters to the editor, books, expert opinions, conference abstracts, articles written in languages other than English, and studies without full-text availability