BACKGROUND
Results on parental burden during the Covid-19 pandemic are predominantly available from online convenience samples. However, these are subject to sample selection bias and, findings cannot necessarily be generalized.
OBJECTIVE
We assessed if results from an online convenience sample are comparable to results of a representative sample regarding parental outcomes during the COVID-19 pandemic. We aimed at identifying those variables (covariates) that explain the difference between the results.
METHODS
We collected data on parental outcomes in August 2020 using an online convenience sample (N= 4967; Mage= 39.11; 87.6 % female) and a sample specific representative of the German adult population with underaged children (N=1024; Mage= 40.9; 52.1% female). We compared sociodemographic data, parent-related risk factors, COVID-19-related experiences, and the results on parental stress, subjective health, parental mental health, general stress, pandemic-related stress, and the occurrence of child maltreatment in the beginning of the COVID-19 pandemic between the two samples. We explored whether differences in outcomes could be explained by our covariates. We examined whether the covariates were good predictors of sample membership.
RESULTS
Parents from the online convenience sample compared to parents from the specific representative sample reported significantly more parental stress (η2= 0.024), decreased subjective health (η2= 0.016), more anxiety and depression symptoms (η2= 0.055), more general stress (η2= 0.044), more often the occurrence (verbal emotional abuse (VEA): π = 0.12; witnessing domestic violence (WDV): π = 0.13) and an increase (VEA: exp(B) = 2.95; WDV: exp(B) = 3.19) of child maltreatment. Sociodemographic data, parent-related risk factors, and COVID-19-related experiences explained differences in parental stress (remaining difference between samples after controlling for covariates η2= 0.002) and subjective health (remaining η2= 0.004) and partially explained differences in parental mental health (remaining η2= 0.016), general stress (remaining η2= 0.014) and child maltreatment (remaining VEA: exp(B) = 2.05; WDV: exp(B) = 2.02) between the two samples. The remaining unexplained differences can possibly be explicated by factors of thematic self-selection not described by the assessed covariates. The covariates predicted sample membership well (R² = 0.56). We seem to have discovered many relevant covariates that describe sample selection.
CONCLUSIONS
Online convenience samples show a considerable sample selection bias that is also relevant for parental outcomes in the Covid-19 pandemic. Therefore, results and implications from online convenience samples cannot be generalized to the general population. We identified relevant covariates that explain most of the differences in results between samples. When conducting studies with convenience sampling, researchers may strive for getting data on relevant covariate distributions in the population they want to draw conclusion on, assess these covariates in the convenience sample and adjust for differences.