Osteopathic Research Web

The usage and quality of sham in randomised controlled trials for low back pain. A structured literature review of manual therapy research.

Item

Title

The usage and quality of sham in randomised controlled trials for low back pain. A structured literature review of manual therapy research.

Author(s)

McGlynn, S

Abstract

Background: Manual therapy RCTs often fail to rank highly in the influential evidence synthesis due to a high risk of bias (ROB). Sham designed RCTs aim to differentiate the specific or nonspecific effects (e.g. placebo, strong time effect correlation to pain regression) of an intervention. A lack of critical understanding exists in the usage and quality of sham in RCT studies investigating LBP. Objective: Explore the latest influential evidence synthesis in manual therapy, for the usage and quality of sham designed RCTs for LBP Design: A structured literature review. Methods: The references of five major evidence reports / systematic reviews (SRs) were subjected to a PICO search strategy. Final studies meeting all inclusion criteria were assessed and individually scored for ROB using a Jaded and bespoke Sham Quality Assessment (SQA) score. Results: From 692 screened references, 17 of 62 LBP RCTs (27%) used sham of any description. Only 11 (65%) eligible sham RCTs for LBP used manual techniques, whilst 6 (35%) employed instrumentation or a handheld device. The final 10 RCTs (901 participants) were arguably underpowered. The data set was skewed by condition (Chronic 70%, Acute 30%) and profession (chiropractic 50%, physical therapy 40% and osteopathic 10%). Overall, the RCTs were of high Jaded quality, but scored poorly in the SQA evaluation. Discussion: 90% of eligible studies concluded the active treatment to be more effective and/or beneficial than sham and/or placebo control. However, these positive outcomes are undermined by methodological weaknesses and inconsistency of findings across individual studies (e.g. pain, disability, quality of life). Several recent studies show evidence of methodological improvement. Conclusion: This study confirms the low quantity and quality of sham designed RCTs for LBP within the influential evidence synthesis. Studies attained high Jadad but poor SQA scores, highlighting a low presence of advocated methodological improvements (e.g. checking for unblinding, using a pre-tested sham). Currently sham RCTs do not offer the strong clinical evidence vital to advocate an intervention for LBP management.

presented at

European School of Osteopathy

Date Accepted

2016

Date Submitted

2.12.2016 17:29:04

Type

osteo_thesis

Language

English

Submitted by:

62

Pub-Identifier

15951

Inst-Identifier

1229

Keywords

Low back pain, Manual therapy, Randomised controlled trials, Sham.

Recommended

0

Item sets

Thesis

McGlynn, S, “The usage and quality of sham in randomised controlled trials for low back pain. A structured literature review of manual therapy research.”, Osteopathic Research Web, accessed May 5, 2025, https://www.osteopathicresearch.org/s/orw/item/530