A meta-analysis of the between-batch variability in the effect of chilling on the salmonella incidence on pig carcasses Conference Paper uri icon

abstract

  • The objective of this work was to study the effect of chilling on the occurrence of Salmonella on pig carcasses at batch level by meta-analysis. Fixed-effects and random-effects metaanalysis were conducted, and the random-effects solution was preferred to account for the significant variability in effect size estimated from 51 sampled batches extracted from 13 primary studies. This study results indicated that chilling reduces the Salmonella incidence on pig carcasses by a mean ratio of ~1.92 (95% CI: 1.36 – 2.70). Multilevel meta-analyses models investigating study characteristics that could explain the heterogeneity (τ2) in the true effect size among sampled batches (τ2=0.373), revealed that ‘total sample size’ and ‘carcass swabbed area’ impact (p<0.05) on the measured effect size of chilling. The fact that swabbed area explained 62% and total sample size 38% of the total heterogeneity in the chilling true effect size, gives rise to an awareness that differences in experimental design greatly affects our substantive conclusion about the effect of chilling on Salmonella recovery. Higher swabbed areas and greater sample sizes led to more precise and greater estimates of the decreasing effect of chilling on Salmonella.

publication date

  • January 1, 2013