Cognitive-behavioral therapy for post COVID-19 condition: A pilot randomized controlled trial, 2026, Sauer et al.

[dave30th]

It seems like they had quite a few. primary outcomes. Did they do any correcting for multiple tests? I didn't see it.

Also, can someone explain to me the difference between the ANCOVA findings on the primary outcomes, and the mixed models for repeated measures (MMRM) results? They seem to get different results on those for the PHQ-15 on somatic symptoms--there's no difference in the primary analysis but there is a difference in the MMRM analysis, which was part of sensitivity analysis but is what they mention in the abstract. Also, they refer to the MMRM results as "post-hoc," which I also don't understand.

Thoughts on these points?

 

[ME/CFS Science Blog]

The study was preregistered at the German Clinical Trials Register (DRKS000333476; registration date: February 1, 2024) a

Anyone able to find the trial registration?

It seems like they had quite a few. primary outcomes. Did they do any correcting for multiple tests? I didn't see it.

Don't see it either and they mention 5 primary outcomes. With correction none would be statistically significant.

Also, can someone explain to me the difference between the ANCOVA findings on the primary outcomes, and the mixed models for repeated measures (MMRM) results? They seem to get different results on those for the PHQ-15 on somatic symptoms--there's no difference in the primary analysis but there is a difference in the MMRM analysis, which was part of sensitivity analysis but is what they mention in the abstract. Also, they refer to the MMRM results as "post-hoc," which I also don't understand.

Post-hoc usually means that it wasn't pre-specified and decided after seeing the results.

Don't think the ANCOVA versus MMRM difference matters much but it does seem like they tried to get more significant results by using another statistical approach.

 

[Nightsong]

Anyone able to find the trial registration?

DRKS00033476 (DRKS.de)

 

[Utsikt]

I’ve added line breaks and bolding:

Primary outcome:
Intensity of body complaints (incl. fatigue, breathing difficulties, circulatory problems, Post-Exertion-Symptoms) with Patient Health Questionnaire - 15 (PHQ-15),

Fatigue Severity Scale (FSS),

Scales "Breathing" and "Circulation" of the Symptom Burden Questionnaire - Long Covid (SBQ-LC),

Scale "Post-Exertion Malaise" of the DePaul Symptom Questionnaire-2 at T0, T1, T2, T3;

Symptom-related thoughts, feelings, and behaviors (symptom burden) with Somatic Symptom Disorder B - Criteria Scale (SSD-12) at T0, T1, T2, T3;

Session rating with Session Rating Scale (SRS) and Group Therapy Session Evaluation form-P/T (GTS-P/T) after each single and group session;

Side effects of treatment with Inventory for the balanced assessment of Negative Effects of Psychotherapy (INEP) at T1 or T2

Secondary outcome:
Disease coping with Brief Illness Perception Questionnaire (B-IPQ) at T0, T1, T2, T3;

Somatosensory Amplification with Somatosensory Amplification Scale (SSAS) at T0, T1, T2, T3;

Construkts of the somatoform spectrum of the Hierarchical Taxonomy of Psychopathology (HiTOP) with short-scale for the somatoform spectrum of the HiTOP zu T0, T1, T2, T3;

Treatment expectations with Credibility/Expectancy Questionnaire (CEQ) at T0;

Anxiety Symptoms with Generalized Anxiety Disorder Scale-7 (GAD-7) at T0, T1, T2, T3;

Depressive Symptoms with Patient Health Questionnaire-9 (PHQ-9) at T0, T1, T2, T3;

Impairments of work productivity and activity with Work Productivity and Activity Impairment Questionnaire (WPAI) at T0, T1, T2, T3

I don’t think they understand what primary means. You’re supposed to pick one, and that’s the one you do the power calculations for.

 

[dave30th]

Post-hoc usually means that it wasn't pre-specified and decided after seeing the results.

Don't think the ANCOVA versus MMRM difference matters much but it does seem like they tried to get more significant results by using another statistical approach.

I was confused about why they called it "post-hoc" because they mentioned the MMRM analysis in their statistical plan without saying it was post-hoc, so I assumed it was part of the overall plan.

As far as the two analyses, I was interested in what the different meanings would be of the two different analyses. They present the MMRM analysis of the PHQ-15 as part of the conclusion in the abstract even though I guess it's not the actual primary analysis. What is its status? It uses the primary outcome data but for a different analysis. So it's a seocndary analysis of the primary outcome results, I guess?