Table 1.
Characteristics and moderators of studies included in the meta-analysis investigating differences in levels of zinc, copper, and iron between healthy controls and subjects with oral submucous fibrosis.
| Author, year (reference) | Biomarker | Age | Men (%) | Sample size (n) | Effect size | |||
|---|---|---|---|---|---|---|---|---|
| Patient | Control | Zinc | Copper | Iron | ||||
| Gupta et al., 1987 [12] | Serum | 35 | 65 | 40 | 10 | 0.112 | 1.264 | —b |
| Varghese et al., 1987 [50] | Serum | 38.85 | 16 | 50 | 50 | −3.800 | −6.541 | —b |
| Rajendran et al., 1992 [49] | Serum | —a | —a | 50 | 50 | —b | —b | −30.170 |
| Anuradha and Devi, 1995 [27] | Plasma | —a | —a | 22 | 22 | −5.436 | −5.730 | −8.461 |
| Luqumun et al., 2003 [50] | Serum | 17–40 | 67 | 15 | 15 | —b | 1.846 | −0.349 |
| Pillai and Burde, 2005 [32] | Serum | 23.40 | —a | 40 | 31 | —b | −0.427 | —b |
| Khanna and Karjodkar, 2006 [52] | Serum | 25–70 | 83 | 30 | 30 | —b | 0.862 | −3.156 |
| Nayak et al., 2010 [65] | Serum | 22–60 | 95 | 20 | 20 | −0.345 | −0.404 | —b |
| Balpande and Sathawane, 2010 [23] | Serum | —a | —a | 30 | 30 | −2.386 | 4.572 | −8.975 |
| Shettar, 2010 [31] | Serum | 29.60 | 80 | 30 | 30 | −1.806 | 0.975 | —b |
| Tadakamadla et al., 2011 [33] | Serum | 18–70 | 90 | 50 | 50 | —b | 1.145 | −0.579 |
| Ayinamudi and Narsimhan, 2012 [63] | Serum | 23–62 | 67 | 15 | 6 | 0.959 | 1.683 | —b |
| Shetty et al., 2012 [53] | Serum | —a | —a | 65 | 21 | —b | —b | −0.452 |
| Shetty et al., 2012 [53] | Saliva | —a | —a | 65 | 21 | —b | —b | −0.399 |
| Hegde et al., 2012 [66] | Serum | 26.85 | 85 | 15 | 60 | —b | —b | −3.501 |
| Neethi et al., 2013 [55] | Serum | 36.53 | 73 | 30 | 30 | −0.521 | 0.758 | —b |
| Khanna et al., 2013 [34] | Serum | 36.85 | —a | 30 | 30 | 0.216 | 0.809 | —b |
| Kode and Karjodkar, 2013 [28] | Serum | —a | —a | 30 | 15 | 1.424 | 0.205 | −0.642 |
| Kode and Karjodkar, 2013 [28] | Saliva | —a | —a | 30 | 15 | 0.497 | 0.512 | −0.517 |
| Kapoora et al., 2013 [24] | Serum | 15–55 | 84 | 50 | 50 | −17.943 | 83.349 | −37.786 |
| Shetty et al., 2013 [54] | Serum | —a | 94 | 50 | 50 | −4.932 | —b | −9.023 |
| Hosthor et al., 2014 [29] | Serum | —a | —a | 30 | 30 | −4.612 | 6.336 | −4.729 |
| Gurprasad et al., 2014 [56] | Serum | 32.5 | 90 | 50 | 35 | —b | —b | −2.853 |
| Shetty et al., 2015 [30] | Saliva | —a | —a | 50 | 50 | −2.485 | 10.989 | −14.582 |
| Yadav et al., 2015 [35] | Saliva | 28.6 | 84 | 50 | 50 | −1.112 | 1.644 | —b |
| Okade et al., 2015 [36] | Saliva | 24.3 | 97 | 30 | 30 | —b | 0.291 | −1.862 |
| Hafeez et al., 2015 [57] | Serum | 49 | 88.8 | 89 | 89 | —b | —b | −0.601 |
| Saurabh et al., 2015 [58] | Serum | 18–45 | 83.3 | 30 | 30 | —b | —b | −3.901 |
| Srilekha, 2015 [37] | Serum | 30–50 | 60 | 22 | 22 | −0.223 | 2.545 | —b |
| Mohammed et al., 2016 [61] | Saliva | 32.73 | 90 | 30 | 30 | —b | 1.772 | —b |
| Kallalli et al., 2016 [59] | Serum | 20–60 | 78 | 30 | 10 | —b | —b | −7.002 |
| Tiwari et al., 2016 [38] | Serum | 41.1 | 75 | 40 | 30 | —b | 2.349 | −2.074 |
| More and Patel, 2016 [26] | Serum | 32.43 | 73 | 30 | 30 | −10.576 | 3.015 | —b |
| Kumar et al., 2016 [64] | Serum | 42.6 | 89 | 35 | 35 | —b | 0.927 | −0.508 |
| Bhardwaj et al., 2016 [62] | Serum | 16–65 | 83 | 40 | 40 | —b | —b | −2.085 |
| Thakur and Guttikonda, 2017 [60] | Serum | —a | —a | 40 | 40 | —b | —b | −1.966 |
aNot reported in the primary study. bNot measured in the primary study.