“…The extent to which the findings of some studies with small sample sizes can be extrapolated to the wider indigenous community is limited, including studies on diabetic retinopathy in the Maori of New Zealand (n = 144) and refractive errors in the Sioux in the United States (n = 184). Twenty-four studies 23,[28][29][30]32,33,36,51,71,72,74,76,79,82,[84][85][86][87][88][89]91,92,103 did not report response rates. Twenty-three studies [20][21][22][24][25][26][27]37,43,47,59,61,65,66,68,69,81,90,95,97,101,102,104 reported a response rate of greater than 70%, with 8 of these 22,24,26,…”