Systematic review and critical appraisal of predictive models for diabetic peripheral neuropathy: Existing challenges and proposed enhancements

Table 1 Characteristics of included studies

Year	Ref.	Country	Design	Type of model (D/V)	Collecting time	Sample size (D/V)	Outcome measure	Age (SD) (years)
2019	Ning et al[11]	China	Case-control study	D	January 2017-June 2018	452/-	DPN occurs	53.62 ± 12.79
2020	Metsker et al[22]	Russia	Cross-sectional study	D, V	July 2010-August 2017	4340/1085	DPN occurs	-
2021	Wu et al[17]	China	Prospective cohort study	D, V	September 2018-July 2019	460/152	DPN occurs	65
2021	Fan et al[21]	China	Real-world study	D, V	January 2010-December 2015	132/33	DPN occurs	-
2022	Zhang et al[18]	China	Case-control study	D, V	February 2017-May 2021	519/259	DPN occurs	D: 57.76 ± 12.95; V: 58.97 ± 12.49
2022	Li et al[10]	China	Retrospective cohort study	D, V	2010-2019	11265/3755	DPN occurs	60.3 ± 10.9
2023	Tian et al[20]	China	Cross-sectional study	D, V	January 2019-October 2020	3297/1426	DPN occurs	-
2023	Li et al[15]	China	Retrospective cohort study	D, V	D: January 2017-December 2020; V: January 2019-December 2020	3012/901	DPN occurs	D: 57.12 ± 12.23; V: 56.60 ± 12.03
2023	Lian et al[16]	China	Retrospective cohort study	D, V	February 2020-July 2022	895/383	DPN occurs	64.5 (55.0–72.0)
2023	Liu et al[19]	China	Retrospective cohort study	D, V	September 2010-September 2020	95604/462	DPN occurs	52.4 ± 12.2
2023	Wang et al[12]	China	Case-control study	D	March 2021-March 2023	500/-	DPN occurs	56.8 ± 10.22
2023	Zhang et al[13]	China	Case-control study	D	April 2019-May 2020	323/-	DPN occurs	55.36 ± 11.25
2023	Gelaw et al[14]	Ethiopia	Prospective cohort study	D	January 2005-December 2021	808/-	DPN occurs	45.6 ± 3.1
2022	Baskozos et al[23]	Multi center	Cross-sectional study	D, V	2012-2019	935/295	Painful or painless DPN occurs	D: 68 (60-74); V: 69 (63-77)

D: Development; V: Validation; DPN: Diabetic peripheral neuropathy.