Complaints of the arm, neck, or shoulder are common musculoskeletal disorders. To gain insight in prognostic factors of complaints of the arm, neck, or shoulder that are associated with recovery, we conducted a systematic review. We included longitudinal prognostic cohort studies that investigated associations between prognostic factors and recovery in terms of symptoms, disability, or sickness absence. Twenty-six papers reporting on 20 cohorts were included following a search of electronic databases (PubMed, Embase, Cinahl, and PsycINFO). The risk of bias (ROB) was independently assessed by 2 reviewers using the Quality in Prognosis Studies tool. Sixteen studies were assessed as having "low" ROB, and 10 studies were assessed as having "high" ROB. Because of heterogeneity in included studies, pooling was not possible. In the qualitative analysis, the number of studies that evaluated a factor, the ROB of each cohort, and consistency of available evidence were taken into account when summarizing the evidence. We examined whether follow-up duration altered the association of prognostic factors with recovery. The results of our best evidence -synthesis showed that for short-term follow-up (studies.