We are sorry, but NCBI web applications do not support your browser and may not function properly. More information

Results: 3

1.
Figure 2

Figure 2. From: Methodological Challenges in Studying Risk Factors for Progression of Knee Osteoarthritis.

A causal diagram of an observational study showing the assessment of the effect of obesity on ROA progression among knees with preexisting ROA at baseline. Conditioning on baseline ROA results in its causes (i.e., obesity and the genetic factor) becoming directly associated, as indicated by a dotted line between obesity and genetic factors, even though these two factors are not associated before the knees developed ROA. Such conditioning opens an alternative path from obesity to ROA progression (i.e., obesity --- genetic factor → ROA progression), thus biasing the effect of obesity on ROA progression.

Yuqing Zhang, et al. Arthritis Care Res (Hoboken). ;62(11):1527-1532.
2.
Figure 3

Figure 3. From: Methodological Challenges in Studying Risk Factors for Progression of Knee Osteoarthritis.

A causal diagram of an observational study showing the assessment of the effect of obesity on ROA progression among knees that have preexisting ROA at baseline and also have follow-up knee radiographs. Conditioning on a common effect, i.e., complete follow-up status (obesity → complete follow-up ← ROA progression) results in its causes (i.e., obesity and ROA progression) becoming directly associated, and opens an alternative path from obesity to ROA progression (i.e., obesity --- ROA progression). Thus, even if there is no association between obesity and ROA progression, conditioning on complete follow-up status tends to introduce a negative association between obesity and ROA progression.

Yuqing Zhang, et al. Arthritis Care Res (Hoboken). ;62(11):1527-1532.
3.
Figure 1

Figure 1. From: Methodological Challenges in Studying Risk Factors for Progression of Knee Osteoarthritis.

A causal diagram of a randomized trial showing assessment of the effect of an intervention regimen (e.g., weight loss) on the risk of ROA progression. Because the intervention regimen in this trial is randomly assigned to the study participants, the intervention regimen is not influenced by either potential confounders (e.g., age, sex, genetic factors, etc.) or previous ROA status, as indicated by the absence of arrows or causal paths directed towards the intervention regimen.

Yuqing Zhang, et al. Arthritis Care Res (Hoboken). ;62(11):1527-1532.

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...
Write to the Help Desk