Understanding the complexity of living with, and managing, secretions in motor neuron disease/amyotrophic lateral sclerosis (MND/ALS/ALS): protocol for a complex intervention systematic review.

introductionMotor neuron disease/amyotrophic lateral sclerosis (MND/ALS/ALS) is an incurable disease which leads to muscle weakness that worsens over time. MND/ALS is highly heterogeneous in its presentation, with many people experiencing a rapidly progressive trajectory of symptoms. Many people living with MND/ALS (plwMND/ALS) experience a combination of flaccidity and spasticity of the muscles involved in speech, swallowing, breathing and coughing. This makes it challenging to deal with the saliva and mucous ('secretions") produced by the body. Failure to manage these problems effectively can lead to accumulation and aspiration of secretions, which may cause pneumonia and respiratory insufficiency. Knowing the best way to treat this problem is a challenge. Systematic reviews report substantive ongoing uncertainty regarding secretions management (SM). Little is known about the comparative effectiveness of secretion management interventions, their impact on quality of life and acceptability for plwMND/ALS and their unpaid/family. METHODS AND ANALYSIS: A complex intervention systematic review of SM for plwMND/ALS and/or their carers will be conducted using an iterative logic model approach, designed in accordance with the principles and guidance laid out in a series of articles published by the Agency for Healthcare Research and Quality on complex intervention reviews . Eight electronic databases will be searched for publications between 1996 and present: Ovid Embase, EBSCO CINAHL, EBSCO Academic Search Ultimate, Scopus, EBSCO PsycInfo, Ovid MEDLINE and the Social Sciences Citation Index. This will be supplemented by hand searching of reference lists of included studies. Two reviewers will independently screen the results for potentially eligible studies using AS Review Lab (a semi-automated machine learning tool). Study selection, data extraction and risk of bias assessment, using Gough's Weight of Evidence Framework, will be independently performed by two reviewers. A framework thematic synthesis approach will be employed to analyse and report quantitative and qualitative data. The reporting will be conducted in line with the Preferred Reporting Items for Systematic Review and Meta-Analysis Complex Intervention Extension Statement and Checklist. ETHICS AND DISSEMINATION: This review will involve the secondary analysis of published information; therefore, ethical approvals are not required. Dissemination will be via presentation at scientific meetings, presentations to MND/ALS support groups and publications in peer-reviewed journals. PROSPERO REGISTRATION NUMBER: CRD42025102364.