The state of population health research performance in the Middle East and North Africa: a meta-research study

Table 1 Univariate regression analysis of systematic review production time trend by publication characteristics

Publication characteristics	Beta	SE	Adjusted R²	p value*	Time trend
Authors
North-South collaboration	2.6	0.4	0.83	0.0004	+
Outside MENA	2.1	0.4	0.79	0.0008	+
Inside MENA and/or neighboring countries	3.4	0.5	0.88	0.0001	+
Journal impact factor (JIF)
0 ≤ JIF < 2	3.3	0.7	0.72	0.0024	+
2 ≤ JIF < 4	3.0	0.6	0.72	0.0021	+
4 ≤ JIF < 6	0.9	0.3	0.44	0.0304	.
JIF ≥ 6	0.8	0.3	0.44	0.0303	.
Yearly number of citations (n)
n < 10	5.5	0.7	0.87	0.0015	+
10 ≤ n < 50	2.2	0.4	0.78	0.0009	+
50 ≤ n < 100	0.3	0.1	0.28	0.0826	.
n ≥ 100	0.0	0.1	− 0.1	0.8887	.
Overall^a	8.1	0.7	0.94	p < 0.0001	+

*p value of the F test. Association statistical significance threshold was at 0.01. ^a The time trend for yearly number of publications was assessed using linear regression in unstratified data. “+”: statistically significant increasing trend. “.”: trend not significant

ISSN: 2046-4053