How do ethological and randomized clinical trials differ in the ...

[londonang]

How do ethological and randomized clinical trials differ in the study of psychiatric patients? What are the advantages and disadvantages of each?
 
  What will be an ideal response?

Question 2

Researchers cannot observe behaviors of interest continuously because it would be too costly.
 
  As a result, they create blocks of time to study the behaviors and hope that the behavior in those blocks presents an accurate picture of what happens during non-observation times. Researchers have investigated optimal ways of using sampling blocks in observational research. How accurate are conclusions drawn from small, medium, and large samples of observations and with random versus cluster sampling?
  What will be an ideal response?

[mammy1697]

Answer to Question 1

A randomized clinical trial (RCT) typically involves creating two or more groups that receive different treatments, either qualitatively different therapies or different dosages of a medication. One group usually involves the accepted treatment for the problem being studied. The dependent measure typically includes relatively simple measurements, such as numbers on a rating scale and degree of improvement in behavior.
An ethological approach would involve studying a more extensive set of behaviors that are more natural, that is, that the participants are likely to show in everyday behavior.
A RCT usually requires a smaller commitment of time by the researcher. On the other hand, the ethological approach provides a richer data set involving naturally occurring behaviors.

Answer to Question 2

In general, as the number of blocks of observations increases, the error in describing the behavior decreases. As Moore (1998) has shown, with few observation blocks (i.e., 4), the inaccuracy in describing behavior patterns was almost four times higher than for a large number of observation blocks (i.e., 30). Thus, it is clear that small samples, which many researchers use, generate inaccurate data.
When researchers decide how to sample, if they use random sampling with short observation periods, they can get accurate data on behaviors by observing as little as 10 percent of the total possible time. Cluster sampling, which involves observations in a few, long periods rather than more, shorter periods, leads to inaccurate data unless the total observation time equals half of the total possible observation time or more.