In: Nursing
The epidemiologists decided to undertake a more rigorous study design to identify if other behaviors or risk factors,apart from drinking water, may be driving the increased blood lead levels observed among children in Flint, Michigan. After receiving parental permission, the investigators conducted a screening of children attending public schools in Flint, Michigan. To determine lead exposure, all children underwent a blood draw for lead testing. Per the current Centers for Disease Control and Prevention recommendation, a blood lead level of 5 μg/dL was used to identify children with abnormally high blood lead levels. The investigators selected a sample of children with blood lead levels ≥ 5 μg/dL and a sample with blood lead levels < 5 μg/dL. The epidemiologists interviewed children and their parents regarding potential exposure to lead from multiple sources, including consumption of certain root vegetables that maybe grown in contaminated soil, source of drinking water, exposure to pesticides in the home, living in a house with peeling paint, living with adults whose job involves battery recycling or processing, etc. as well as socioeconomic characteristics of the family (highest level of education attained by the parents, annual income, race/ethnicity, etc.).
What type of epidemiological study design did the authors undertake? Explain your answer. Define recall bias and describe how it may specifically play a role in this study. Do you think social desirability bias could play a role in this particular study? Why or why not?
EPIDEMIOLOGICAL STUDY DESIGN
Epidemiology is the study to investigate the distribution & cause of the diseases in population. Therefore they are generally conducted to investigate causes of different diseases in either PROSPECTIVE APPROACH : Named Cohort studies ( causes to effect ) or RETROSPECTIVE APPROACH : Named Case control studies ( effect to cause )
Here the researcher used CASE CONTROL STUDIES.
EXPLANATION :
Here the researcher is trying to identify other behaviour or risk factors, apart from drinking water leading to the increased blood levels among children in Flint, & Michigan.
Here the risk factors are investigated after the occurrence of a problem ( increase in blood levels )
Chances of SOCIAL DESIRABILITY BIAS
The tendancy of survey respondents to answer the questions in a manner that will be viewed favourably by others.
Includes ;
Over reporting good behaviour
Under reporting bad behaviour
Sharing questions among the samples
Chances in this case
Here the interview method is used by the researcher for data collection
1. Students & parents may collect questions from the people who already undergone the interview before them &ay try to answer in socially desirable manner.
2. Giving wrong answers to maintain socioeconomic status
RECALL BIAS
It is a systematic error caused by defferentiated in the accuracy of completeness of the recollections retrieved by study participants regarding the events or experiences from the past
Here,
Participants have to answer accurately about the exposure of lead from multiple sources such as contaminated soil, consumption of certain root Vegetables & exposure to pesticides & peeling paints.
If they are unable to recall about prior exposure, the study gets biased.