Table 3.
Unadjusted meta-regression analyses for the individual theory coding items, six categories of theory use, and use of theory scores.
| Theory coding scheme covariates (item or category number) | B (SE) | P value | 95% CI | Adjusted R2 (%) | I2 (%) | Bayes factor |
| Theory or model of behavior mentioned (I1) | 9.73 (14.63) | .51 | −19.84 to 39.31 | −4.90 | 78.09 | 0.36 |
| Targeted construct mentioned as predictor of behavior (I2) | 24.17 (14.09) | .09 | −4.30 to 52.64 | 2.27 | 78.13 | 0.22 |
| Intervention based on single theory (I3) | 12.92 (17.60) | .47 | −22.64 to 48.49 | −4.44 | 78.08 | 0.40 |
| Theory or predictors used to select or develop intervention techniques (I5) | 18.25 (14.57) | .22 | −11.20 to 47.69 | −3.43 | 78.15 | 0.27 |
| All intervention techniques are explicitly linked to at least one theory-relevant construct or predictor (I7) | −3.73 (19.91) | .85 | −43.98 to 36.51 | −4.86 | 76.50 | 0.73 |
| At least one, but not all, of the intervention techniques are explicitly linked to at least one theory-relevant construct or predictor (I8) | 26.39 (15.34) | .09 | −4.60 to 57.39 | 10.54 | 77.49 | 0.23 |
| All theory-relevant constructs or predictors are explicitly linked to at least one intervention technique (I10) | 8.53 (19.81) | .67 | −31.60 to 48.46 | −5.82 | 78.14 | 0.51 |
| At least one, but not all, of the theory-relevant constructs or predictors are explicitly linked to at least one intervention technique (I11) | 18.79 (15.99) | .25 | −13.54 to 51.11 | −3.45 | 78.15 | 0.30 |
| Theory-relevant constructs are measured: post intervention (I12a) | −14.67 (15.81) | .36 | −46.62 to 17.28 | 1.42 | 76.37 | 1.18 |
| Theory-relevant constructs are measured: post and pre intervention (I12b) | −13.78 (16.88) | .42 | −47.90 to 20.33 | −1.67 | 76.94 | 1.09 |
| Changes in measured theory-relevant constructs or predictor (I13) | −33.04 (17.48) | .07 | −68.37 to 2.28 | 16.92 | 74.82 | 3.50 |
| Mediational analysis of constructs or predictors: mediator predicts the dependent variable (I14a) | −7.77 (20.24) | .70 | −48.68 to 33.15 | −3.13 | 76.43 | 0.84 |
| Mediational analysis of constructs or predictors: intervention does not predict the dependent variable when controlling the independent variable (I14c) | −21.88 (24.11) | .37 | −70.61 to 26.86 | 4.48 | 75.41 | 1.29 |
| Mediational analysis of constructs or predictors: mediated effect is statistically significant (I14d) | −7.77 (20.24) | .70 | −48.68 to 33.14 | −3.13 | 76.43 | 0.84 |
| Results discussed in relation to theory (I15) | 1.59 (16.08) | .92 | −30.91 to 34.08 | −6.81 | 77.35 | 0.54 |
| Appropriate support for theory (I16) | −8.73 (19.43) | .66 | −48.01 to 30.55 | −2.11 | 76.33 | 0.87 |
| Reference to underpinning theory (C1) | 7.19 (5.89) | .23 | −4.72 to 19.10 | −1.55 | 78.08 | 0.12 |
| Targeting of relevant theoretical constructs (C2) | 3.94 (2.97) | .19 | −2.06 to 9.93 | −4.08 | 78.12 | 0.06 |
| Using theory to select recipients or tailor interventions (C3) | 13.30 (27.27) | .63 | −41.81 to 68.42 | −7.21 | 77.67 | 0.60 |
| Measurement of constructs (C4) | −7.58 (8.41) | .37 | −24.58 to 9.42 | 0.19 | 76.61 | 0.79 |
| Testing of theory: mediation effects (C5) | −2.09 (2.53) | .41 | −7.20 to 3.02 | 2.29 | 75.71 | 0.24 |
| Total use of theory | 0.39 (1.37) | .78 | −2.38 to 3.15 | −7.46 | 77.58 | 0.05 |