Interpreting Mediation results

Posted by psy_vm on Jul 24, 2014; 7:17am
URL: http://spssx-discussion.165.s1.nabble.com/Interpreting-Mediation-results-tp5726809.html

Hello,

I have a few questions regarding interpretation of my results for Mediation using Hayes' Process macro. The key point for finding significance is to see that the Class Interval does not include zero. However, in my mediation model, although the indirect effect CI doesn't include zero, the initial Models's CI (for bcope_ma, under Duration) includes zero. Should I still count my indirect effects as significant even though initial model for mediation is not significant?

Results pasted below. Please Help! Thanks in advance!

Model = 4
    Y = qoltot
    X = duration
    M = bcope_ma

Sample size
         70

**************************************************************************
Outcome: bcope_ma

Model Summary
          R        R-sq          F            df1        df2          p
      .1830      .0335     2.3550     1.0000    68.0000      .1295

Model
                   coeff          se              t          p       LLCI       ULCI
constant    22.5169     1.3151    17.1223      .0000    19.8927    25.1411
duration     -.0388      .0253    -1.5346      .1295     -.0893      .0117

**************************************************************************
Outcome: qoltot

Model Summary
          R          R-sq          F          df1        df2          p
      .3234      .1046     3.9140     2.0000    67.0000      .0247

Model
                    coeff         se          t               p       LLCI         ULCI
constant      91.2951     9.5536     9.5560      .0000    72.2258   110.3643
bcope_ma    -1.0460      .3823    -2.7364      .0079    -1.8091     -.2830
duration      .0059          .0811      .0725      .9425     -.1559      .1677

************************** TOTAL EFFECT MODEL ****************************
Outcome: qoltot

Model Summary
          R        R-sq           F           df1        df2          p
      .0674      .0045      .3102     1.0000    68.0000      .5794

Model
                  coeff         se            t               p       LLCI       ULCI
constant    67.7413     4.3387    15.6134      .0000    59.0836    76.3990
duration      .0465      .0834      .5570      .5794     -.1200      .2129

***************** TOTAL, DIRECT, AND INDIRECT EFFECTS ********************

Total effect of X on Y
     Effect         SE             t          p           LLCI       ULCI
      .0465      .0834      .5570      .5794     -.1200      .2129

Direct effect of X on Y
     Effect         SE          t             p         LLCI       ULCI
      .0059      .0811      .0725      .9425     -.1559      .1677

Indirect effect of X on Y
                    Effect    Boot SE   BootLLCI   BootULCI
bcope_ma      .0406      .0311      .0009      .1240

Partially standardized indirect effect of X on Y
                   Effect    Boot SE   BootLLCI   BootULCI
bcope_ma      .0022      .0016      .0000      .0068

Completely standardized indirect effect of X on Y
                   Effect    Boot SE   BootLLCI   BootULCI
bcope_ma      .0589      .0411      .0017      .1650

Ratio of indirect to total effect of X on Y
                  Effect    Boot SE   BootLLCI   BootULCI
bcope_ma      .8736   149.0933      .1603    53.5001

Ratio of indirect to direct effect of X on Y
                  Effect    Boot SE   BootLLCI   BootULCI
bcope_ma     6.9093    17.9156     3.4423   275.8767

R-squared mediation effect size (R-sq_med)
                 Effect    Boot SE   BootLLCI   BootULCI
bcope_ma      .0045      .0173     -.0184      .0543

Preacher and Kelley (2011) Kappa-squared
             Effect    Boot SE   BootLLCI   BootULCI
bcope_ma      .0601      .0401      .0066      .1692

Normal theory tests for indirect effect
     Effect         se          Z          p
      .0406      .0318     1.2753      .2022

******************** ANALYSIS NOTES AND WARNINGS *************************

Number of bootstrap samples for bias corrected bootstrap confidence intervals:     1000

Level of confidence for all confidence intervals in output:    95.00

NOTE: Some cases were deleted due to missing data.  The number of such cases was:  33