A study enrolled 517 children aged two to five years with a diagnosis of autism spectrum disorder and 315 control children of the same age group but without such a diagnosis. Information was collected about metabolic conditions of the mothers at the time of their pregnancy, such as type 2 diabetes, hypertension, and obesity. Metabolic conditions during pregnancy tended to be more frequent among the mothers of children with autism spectrum disorder than among mothers of control children.

Complete Question:

A study enrolled 517 children aged two to five years with a diagnosis of autism spectrum disorder and 315 control children of the same age group but without such a diagnosis. Information was collected about metabolic conditions of the mothers at the time of their pregnancy, such as type 2 diabetes, hypertension, and obesity. Metabolic conditions during pregnancy tended to be more frequent among the mothers of children with autism spectrum disorder than among mothers of control children. This is

This is an observational study with a case-control design  

Explanation:

An Observational study is a study in which researchers observe the outcomes of an intervention, a test, a treatment or a risk factor on a test population without intervening or influencing what part of the population is exposed.  

There are two types of observational studies:

1.Cohort studies

2.Case control studies

The cohort study is a type of observational study that identifies a population  exposed to a particular factor and compares them with another group that was not exposed to that factor, measuring and comparing outcomes in the two groups.

The case-control study involves using a different strategy of sampling whereby the population that develops outcomes from exposure to a particular factor is compared with those that did not, after exposure.

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