Table 3. Results of moderator analyses for criterion-related validity correlation coefficients for estimating hamstring extensibility across all sit-and-reach test protocols potentially affected by moderator effects Moderator Effect K n N rc rp 95% CIa 95% CVb % of variancec Q statistic Gender of participants Classic sit-and-reach Males 19 21 1,493 .62 .64 .50, .78 .46, .82 38.28 54.86* Females 18 20 1,361 .68 .70 .58, .82 .49, .91 25.06 79.80* Modified sit-and-reach Males 7 7 469 .53 .55 .38, .71 .26, .83 26.80 59.70* Females 6 6 447 .60 .62 .48, .76 .53, .72 68.72 23.28* Back-saver sit-and-reach Males 8 8 490 .57 .59 .42, .75 .48, .69 71.70 11.16 Females 9 9 613 .58 .60 .45, .75 .33, .87 24.05 37.42* Unilateral sit-and-reach Males 2 2 182 .59 .61 .48, .74 .61, .61 100.00 .72 Females 2 2 196 .63 .66 .55, .77 .47, .85 25.66 7.80* Chair sit-and-reach Males 1 1 32 .76 .83 .71, .94 .83, .83 100.00 .00 Females 2 2 150 .39 .41 .22, .60 –.16, .99 9.79 20.42 Age of participants Classic sit-and-reach Children 8 14 1,173 .66 .67 .55, .79 .47, .87 26.28 53.27* Adults 20 33 2,308 .64 .68 .55, .80 .43, .92 21.22 155.50* Modified sit-and-reach Children 1 2 87 .31 .32 .05, .59 .32, .32 100.00 1.34 Adults 8 14 971 .56 .58 .42, .74 .37, .79 35.13 45.55* Back-saver sit-and-reach Children 2 4 257 .58 .59 .43, .75 .45, .74 55.88 7.16 Adults 8 14 901 .56 .59 .43, .75 .36, .82 33.38 41.94* Unilateral sit-and-reach Children - - - - - - - - - Adults 2 4 378 .61 .64 .52, .76 .51, .76 47.43 8.43* Chair sit-and-reach Children - - - - - - - - Adults 2 3 182 .45 .49 .29, .68 –.11, 1.00 9.50 31.57* Level of hamstring extensibility Classic sit-and-reach Low 15 16 1,129 .60 .63 .48, .77 .41, .84 30.79 51.97* High 19 25 1,984 .67 .70 .59, .81 .46, .94 18.39 135.91* Modified sit-and-reach Low 4 5 355 .51 .53 .36, .70 .24, .82 24.87 64.35* High 7 10 648 .55 .58 .41, .74 .36, .79 37.42 42.75* Back-saver sit-and-reach Low 5 6 433 .54 .57 .41, .72 .31, .82 27.37 21.92* High 7 11 670 .59 .61 .45, .77 .44, .79 45.34 24.26* Unilateral sit-and-reach Low 1 1 120 .56 .58 .47, .70 .58, .58 100.00 .00 High 2 3 258 .63 .66 .55, .78 .51, .81 38.22 7.85* Chair sit-and-reach Low 2 2 134 .33 .35 .14, .56 –.13, .83 16.42 12.18* High 1 1 48 .81 .86 .79, .94 .86, .86 100.00 .00 , number of studies; , number of s; , total sample size; , overall weighted mean of corrected for sampling error only; , overall weighted mean of corrected for sampling error and measurement error; 95% confidence interval; 95% credibly interval Percentage of variance accounted for by statistical artefacts including sampling error and measurement error of sit-and-reach tests. * < 0.05 †  Because some studies mixed genders or hamstring extensibility levels were missed, the overall for these categories is lower for some sit-and-reach tests.