Skip to ContentSkip to Navigation
About usFaculty of Science and EngineeringResearchGRIPNews and activities

Self-controlled designs to control confounding

01 December 2015

The best available evidence for decision-making on interventions will often come from observational studies. Given the vulnerability of observational studies to confounding, complete and transparent reporting on confounding is necessary to enable readers to assess the validity of study findings. In his thesis Koen Pouwels assessed whether the reporting of confounding improved after the publication of the STROBE guideline. The reporting of confounding was similar before and after the publication of this reporting guideline and was not better in journals that more actively endorsed the guideline. Hence, research into the development and evaluation of strategies to improve the quality of reporting and adherence to reporting guidelines is needed rather than adding another guideline to the steadily increasing pile.

One of the more novel developments with regard to the control of confounding in observational studies is the application of a self-controlled design. Pouwels applied and empirically compared various available self-controlled designs. Although self-controlled methods seemed to be able to control confounding better in situations where strong unmeasured time-invariant confounding was present, such designs are often applied when it is likely that assumptions underlying these designs are violated. Discrepancies between parallel group designs and self-controlled designs could be predicted by failure to meet assumptions of the self-controlled designs. Therefore, Pouwels recommends to apply self-controlled designs when there are concerns about unmeasured confounders, but also to verify whether assumptions are likely met and in case of uncertainty to apply sensitivity analyses.

Dissertation: http://hdl.handle.net/11370/1b5ed2b5-50a9-4d30-a50f-b772d23fce48

PhD ceremony:

K.B. Pouwels, MSc

When:

December 04, 2015

Start:

16:15

Promotor:

prof. dr. E. (Eelko) Hak

Where:

Academy building RUG

Faculty:

Mathematics and Natural Sciences

Last modified:17 June 2019 5.37 p.m.
printView this page in: Nederlands

More news

  • 11 July 2019

    Major companies’ annual reports too vague about climate impact

    Many major Dutch companies publish extensive information about climate impact in their annual reports. However, very few companies provide concrete, detailed information about their own CO2 emissions, the impact of climate change on their business...

  • 08 July 2019

    UG permanently closes Yantai project

    The University of Groningen (UG) has permanently closed the project aimed at creating a branch campus in Yantai. Discussions were held with China Agricultural University, the city of Yantai and the Province of Shandong.

  • 03 July 2019

    Cheap train tickets boost public transport use but reduce customer satisfaction

    Offers of cheap single train tickets through retailers such as Kruidvat or Etos have a positive impact on the number of kilometres travelled by rail. This impact is much bigger than that of more general TV, newspaper or magazine advertising. However,...