## Table 7 |
|||||||||

Results of the mixed-effects meta-regressions for the continuous moderator variables
on the effect sizes obtained from measures of knowledge in the posttest |
|||||||||

Cluster / Moderator variable |
k |
Min. |
Max. |
Mean |
SD |
b_{j} |
Q_{R} |
Q_{E}(df) |
R^{2} |

(A) Treatment characteristics: | |||||||||

Treatment duration (weeks) | 15 | 1.0 | 96.0 | 17.5 | 32.1 | −0.012 | 6.60** | 144.46(13)*** | 0.430 |

Treatment intensity (hours/week) | 12 | 0.2 | 2.4 | 0.9 | 0.6 | −0.059 | 0.03 | 142.28(10)*** | 0.0 |

Treatment magnitude (total hours) | 12 | 0.2 | 19.0 | 5.0 | 5.0 | −0.001 | 0.00 | 128.72(10)*** | 0.026 |

(B) Subject characteristics: | |||||||||

Mean age (years) | 14 | 8.0 | 12.0 | 1.2 | 1.2 | 0.130 | 0.48 | 345.18(12)*** | 0.0 |

Gender (% male) | 14 | 45.8 | 58.2 | 3.7 | 3.7 | 0.029 | 0.20 | 384.63(12)*** | 0.0 |

(C) Methodological characteristics: | |||||||||

Differential attrition | 16 | 0.0 | 0.033 | 0.004 | 0.009 | −24.205 | 1.14 | 355.39(14)*** | 0.0 |

Quality score | 16 | 3.4 | 7.5 | 6.0 | 1.1 | 0.282 | 2.71 | 267.05(14)*** | 0.177 |

(D) Extrinsic characteristic: | |||||||||

Publication year | 16 | 1984 | 2011 | 2003 | 8.4 | −0.014 | 0.28 | 370.92(14)*** | 0.0 |

* *p* < .05. ** *p* < .01. *** *p* < .001. *k*: number of studies. Min. and Max.: minimum and maximum values of the moderator variable.
*SD*: standard deviation of the moderator variable. *b*_{j}: unstandardized regression coefficient associated to the moderator variable. *Q*_{R}: statistic for testing the significance of the moderator variable. *Q*_{E}: statistic for testing the model misspecification. *df*: degrees of freedom. *R*^{2}: proportion of variance accounted for by the moderator variable.

Calvo-Muñoz * et al.*

Calvo-Muñoz * et al.* *BMC Musculoskeletal Disorders* 2012 **13**:152 doi:10.1186/1471-2474-13-152