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andreyandreev [35.5K]
3 years ago
3

**Question 1\.\** The data were gathered by the following procedure, reported in the study. "Between January and June 1998, pare

nts of children aged 2-16 years [...] that were seen as outpatients in a university pediatric ophthalmology clinic completed a questionnaire on the child’s light exposure both at present and before the age of 2 years." Was this study observational, or was it a controlled experiment? Explain.
Mathematics
1 answer:
eduard3 years ago
8 0

Answer:

OBSERVATIONAL

Step-by-step explanation:

Let`s see the two kind of experiments mentioned:

  • Observational experiments: are those where individuals are observed or certain outcomes are measured. There is no intervention by the scientist, for example: no treatment at all is given
  • Controlled experiments: Are those experiments that are directly manipulaed by the sciencist in order to study the controlled variable's reaction or change.

In this case, the patient's parent only answer a questionnairewith no intervention from the doctors into the pacients at all, so it's an observational  experiment

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Answer:

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Step-by-step explanation:

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Step-by-step explanation:

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Step-by-step explanation:

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<h2>_______________</h2>

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