Fish and Marine Omega-3 Polyunsatured Fatty Acid Consumption and Incidence of Type 2 Diabetes: A Systematic Review and Meta-Analysis

Table 2

Subgroup analysis to investigate heterogeneity source in meta-analysis.

Fish/seafood intake	Publications	Pooled RR, ^1𝑃 value	Heterogeneity ^2𝑃 value	^3𝑃 value	Marine LC n-3 PUFA	Publications	Pooled RR, ^1𝑃 value	Heterogeneity ^2𝑃 value	^3𝑃 value
Ethnicity				0.18	Ethnicity				0.064
Asian (Chinese, Japanese)	2 [12, 13]	0.87, 0.006	0.83		Asian (Chinese, Japanese)	2 [13, 19]	0.87, 0.005	0.42
US/European	8 [14–18, 20–22]	1.10, 0.22	0.0001		US/European	4 [14, 15, 18, 20]	1.27, <0.00001	0.7
Length of follow-up (years)				0.17	Length of follow-up (years)				0.064
<10	4 [13, 16, 17, 21]	0.91, 0.11	0.16		<10	2 [13, 19]	0.87, 0.005	0.42
≥10	6 [13–15, 18, 20, 22]	1.17, 0.04	0.02		≥10	4 [14, 15, 18, 20]	1.27, <0.00001	0.7
Assessment of T2D				0.18	Assessment of T2D				NA
Confirmed by physician/phone interview/hospital records	3 [16, 21, 22]	0.91, 0.28	0.2		Confirmed by physician/phone interview/hospital records	0	NA	NA
Confirmed by standard criteria or plasma glucose measurement	7 [12–15, 17, 18, 20]	1.10, 0.31	<0.0001		Confirmed by standard criteria or plasma glucose measurement	6 [13–15, 18–20]	1.09, 0.36	<0.00001
Sample size				0.51	Sample size				1
<10000	3 [18, 20, 22]	1.14, 0.26	0.29		<10000	2 [18, 20]	1.18, 0.11	0.53
≥10000	7 [12–17, 21]	1.01, 0.88	<0.0001		≥10000	4 [13–15, 19]	1.07, 0.57	<0.0001
Quality score				0.18	Quality score				0.33
High (9–12)	2 [12, 13]	0.87, 0.006	0.83		High (9–12)	1 [13]	0.85, NA	NA
Moderate (5–8)	8 [14–18, 20–22]	1.1, 0.22	0.0001		Moderate (5–8)	5 [14, 15, 18–20][16, 17, 20–22]	1.17, 0.01	0.03

¹𝑃 value calculated by 𝑍 statistic.
²𝑃 value calculated by 𝐼² statistic.
³𝑃 value calculated by Mann-Whitney 𝑈 test.