Table 1.

Characteristics of the studies included in this review.

	Author	Publication Year	Country	Design	Subtypes
1.	Brown et al. [29]	2022	The USA	Cross-sectional study	Chronic primary cervical pain (CPCP)
2.	Brunner et al. [30]	2018	Germany	Cross-sectional study	Chronic primary low back pain (CPLBP)
3.	Clark et al. [31]	2019	New Zealand	Cross-sectional study	Chronic primary low back pain (CPLBP)
4.	Coppieters et al. [32]	2021	Belgium	Cross-sectional study	Chronic primary cervical pain (CPCP)
5.	Day et al. [33]	2019	Australia	Cross-sectional study	Chronic primary low back pain (CPLBP)
6.	Fujii et al. [34]	2018	Japan	Cross-sectional study	Chronic primary low back pain (CPLBP)
7.	Ho et al. [35]	2019	Norway	Cross-sectional study	Chronic primary low back pain (CPLBP)
8.	Kasahara et al. [36]	2021	Japan	Cross-sectional study	Chronic primary low back pain (CPLBP)
9.	Kim et al. [37]	2019	The USA	Cross-sectional study	Chronic primary low back pain (CPLBP)
10.	Ma et al. [38]	2020	China	Cross-sectional study	Chronic primary low back pain (CPLBP)
11.	Moreira et al. [39]	2021	Brazil	Cross-sectional study	Chronic primary low back pain (CPLBP)
12.	Neumann and Hampel [40]	2022	Germany	Longitudinal study	Chronic primary low back pain (CPLBP)
13.	Pakpour et al. [41]	2018	Iran	Longitudinal study	Chronic primary low back pain (CPLBP)
14.	Richards et al. [42]	2018	Australia	Cross-sectional study	Chronic primary low back pain (CPLBP)
15.	Rogers et al. [43]	2022	The USA	Cross-sectional study	Chronic primary low back pain (CPLBP)
16.	Rumble et al. [44]	2021	The USA	Longitudinal study	Chronic primary low back pain (CPLBP)
17.	Shen et al. [45]	2019	The USA	Cross-sectional study	Chronic primary low back pain (CPLBP)
18.	Skarpsno et al. [46]	2020	Norway	Longitudinal study	Chronic primary low back pain (CPLBP)
19.	Tabira et al. [47]	2020	Japan	Cross-sectional study	Chronic primary low back pain (CPLBP)
20.	Weiner et al. [48]	2019	The USA	Cross-sectional study	Chronic primary low back pain (CPLBP)