Table 2.

Characteristics of the included studies, part two: sampling technique, data collection tool, sample size, response rate, mean age, and low back pain cases.

Authors	Sampling technique	Data collection tool	Sample	Response rate (%)	Mean age and SD	Gender		LBP cases
						F	M
Wami et al. [57]	Systematic	IAQ∗	422	100	26.71 ± 4.9	388	34	245
Mekonnen1 [58]	Systematic	IAQ∗	418	99	31.39 ± 7.01	233	185	266
Mekonnen2 [59]	Systematic	IAQ∗	429	98.8	26.38 ± 4.78	56	373	239
Abebe et al. [60]	Simple	IAQ	263	90.7	33.5 ± 6.7	126	137	109
Abebaw et al. [61]	Cluster and simple	IAQ∗	771	93.2	33 ± 10.63	378	393	340
Yosef et al. [62]	Systematic	IAQ∗	400	94.8	37.7 ± 9.13	0	400	260
Kebede et al. [63]	Simple	SAQ∗	611	93	40 ± 9.38	331	280	457
Beyen et al. [64]	Stratified	SAQ	602	90.9	38 ± 11.02	191	411	324
Belay et al. [65]	Simple	SAQ	395	91.9	30.6 ± 8.4	285	110	181
Wanamo et al. [66]	Systematic	IAQ∗	422	100	35.28 ± 10.06	NR	271
Assefa [67]	Convenience	SAQ∗	316	82.3	31.6 ± 8.4.	193	123	147
Tefera et al. [68]	Multistage	IAQ∗	814	99	14–17 years	221	593	398
Tafese [69]	Simple	IAQ∗	660	100	30.1 ± 8.1	211	449	384
Tafese et al. [70]	NR	IAQ∗	422	100	26.9 ± 7.2	370	52	274
Assefa [71]	Simple	IAQ∗	422	100	26 (MA)	112	310	262
Yitayeh et al. [72]	Census	IAQ∗	389	NR	30 ± 5.8	209	180	175
Lamina et al. [73]	Simple	SAQ	100	83	NR	NR	60
Henok and Bekele [74]	Convenience	IAQ∗	422	100	>15	422	0	255
Lette et al. [75]	Simple	SAQ	410	97.2	31.32 ± 7.54	NR	105
Girma [76]	Stratified and simple	IAQ∗	422	100	29 (MA)	355	67	184
Bedru [77]	Multistage	IAQ∗	599	98.3	25 (MA)	472	127	428
Etana [78]	Simple	IAQ∗	335	98	31 ± 5.27	80	255	181
Regassa et al. [79]	Systematic	SAQ	301	90.4	NR	142	159	124
Hailu [80]	Simple	IAQ∗	412	97.6	28.6 ± 5.7	155	257	148
Zungu and Nigatu [81]	Randomly	SAQ	294	93	31	43	251	NR
Deksisa et al. [82]	Proportional	IAQ	300	NA	30 (MA)	132	168	NA
Yehualaw [83]	Census	IAQ∗	410	91.5	28.67 ± 5.46	306	104	340
Teklu [84]	Simple	IAQ∗	512	95	NR	102	410	335
Mijena et al. [85]	Simple	SAQ	404	96	30.4 ± 8.733	225	179	154
Abir et al. [86]	Simple and purposive	IAQ and DR	343	NR	NR	212	131	11
Jeon and Jeon [87]	Cluster	IAQ	116	NR	49	43	73	46
Delele et al. [88]	Multistage	IAQ∗	723	85.6	11.5 ± 2.7	423	297	50

IAQ: interviewer-administered questionnaire; F: female; SAQ: self-administered questionnaire; DR: document review; NR: not reported; M: male; MA: median age; SD: standard deviation; NA: not applicable.^∗Standardized Nordic questionnaire for the analysis of musculoskeletal symptoms; .