Background : The influence of nutrition on the oral microbiota has been discussed in the literature, but usually only changes of the mean values are reported. This paper focuses on the variability of patients' reactions.
Methods : Two types of inter-individual variability in such studies and statistical models to estimate them are introduced. Through smart presentation of the estimates from the studies, a better understanding of the data can be obtained. Random effects meta-analyses are used to analyse the heterogeneity in variability across different bacteria.
Results : For the nutrition individually chosen by the participants, we observed an inter-individual variability of the bacterial concentration of three log steps. Given that we found no evidence of heterogeneity in variability across different bacteria, the results can be used to offer recommendations for future studies and compute the number of cases needed.
Conclusions : For studies measuring the concentration change of bacteria as a reaction to nutrition change, the use of replications and analysis of the variability is recommended.