Table 2.

Focused PICOS used to define the narrowed research question “Are there dietary supplements/ingredients that can safely mitigate chronic pain in adults (18+ years old) with musculoskeletal disorders?”

Population	Adults (18+ years) with chronic pain due to musculoskeletal disorders. Chronic pain was defined as ongoing or recurrent pain, lasting beyond the usual course of acute illness or injury (i.e., more than 3 months and occurring at least half of the days over the past 6 months) and which adversely affects the individual’s well-being [3, 24]. Musculoskeletal pain was defined as pain affecting the bones, muscles, ligaments, or disorders of the muscles, nerves, tendons, joints, cartilage, and disorders of the nerves, tendons, muscles, and supporting structures of the upper and lower limbs, neck, and lower back that are caused, precipitated, or exacerbated by sudden exertion or prolonged exposure to physical factors such as repetition, force, vibration, or awkward posture [25, 26]. Note that headaches/migraines and MSK pain conditions resulting from another disease or injury (e.g., fracture, contusion, abrasion, laceration) were excluded.
Intervention	Any single or multiple (e.g., combination of ingredients) dietary ingredient(s).
Control/comparison	Sham, no treatment and/or active comparator.
Outcome(s)	Pain, physical function, sleep, mood (anxiety/depression), stress, cognitive performance, global health, health-related quality of life, behavior, resource use, adverse events.
Study design	Peer-reviewed systematic reviews/meta-analyses and/or randomized controlled trials presented in the English language.

MSK = musculoskeletal; PICOS = Population, Intervention, Comparison, Outcomes and Study Designs strategy.