The Duval and Tweedie's Trim and fill procedure pointed to the possibility of some publication bias.
More specifically, this method suggested 30 studies were missing and that the point estimate and 95 percent confidence interval using the Trim and Fill imputed point estimate was 0.12(+-.08).
In summary. although these tests provide some evidence of potential publication bias in the data, there are other sources of asymmetry in funnel plots.
Among those is true heterogeneity in the effect (e.g. caused by gender and/or age difference across studies).
Thus, Further analyses investigating the sources of the heterogeneity via moderator analyses were warranted.