The power of an interrupted time-series design can be increased ...

[SO00]

The power of an interrupted time-series design can be increased by
 
  A) adding one or more comparison groups.
  B) studying important legal and regulatory phenomena, such as child car seats.
  C) random assignment of participants to groups.
  D) asking participants to practice regression to the mean.

Question 2

In an interrupted times-series study on the effect of a reduced speed limit, the change in the time graph must
 
  A) be a sharp drop followed by a gradual increase back to the baseline to be interpreted as anything other than normal fluctuation.
  B) be slight or gradual at the time of the interruption to be interpreted as anything but normal fluctuation.
  C) be quite sharp at the time of the interruption to be interpreted as anything other than normal fluctuation.
  D) be a sharp increase followed by a sharp decrease to be interpreted as anything but normal fluctuation.

[Dinolord]

Answer to Question 1

Answer: A

Answer to Question 2

Answer: C

[SO00]

TYSM

[Dnite]

Excellent