Format

Send to

Choose Destination
Prev Sci. 2015 Oct;16(7):967-77. doi: 10.1007/s11121-015-0569-4.

Research Designs for Intervention Research with Small Samples II: Stepped Wedge and Interrupted Time-Series Designs.

Author information

1
University of Alaska Fairbanks, Fairbanks, AK, USA. ctfok@alaska.edu.
2
University of Illinois at Chicago, Chicago, IL, USA.
3
University of Minnesota Medical School, Duluth Campus, Duluth, MN, USA.

Abstract

The stepped wedge design (SWD) and the interrupted time-series design (ITSD) are two alternative research designs that maximize efficiency and statistical power with small samples when contrasted to the operating characteristics of conventional randomized controlled trials (RCT). This paper provides an overview and introduction to previous work with these designs and compares and contrasts them with the dynamic wait-list design (DWLD) and the regression point displacement design (RPDD), which were presented in a previous article (Wyman, Henry, Knoblauch, and Brown, Prevention Science. 2015) in this special section. The SWD and the DWLD are similar in that both are intervention implementation roll-out designs. We discuss similarities and differences between the SWD and DWLD in their historical origin and application, along with differences in the statistical modeling of each design. Next, we describe the main design characteristics of the ITSD, along with some of its strengths and limitations. We provide a critical comparative review of strengths and weaknesses in application of the ITSD, SWD, DWLD, and RPDD as small sample alternatives to application of the RCT, concluding with a discussion of the types of contextual factors that influence selection of an optimal research design by prevention researchers working with small samples.

KEYWORDS:

Interrupted time-series design; Research design; Small samples; Stepped wedge design

PMID:
26017633
PMCID:
PMC4581909
DOI:
10.1007/s11121-015-0569-4
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Springer Icon for PubMed Central
Loading ...
Support Center