Article Text

Download PDFPDF
Airway clearance research in CF: the ‘perfect storm’ of strong preference and effortful participation in long-term, non-blinded studies
  1. Eleanor Main
  1. Correspondence to Dr Eleanor Main, Portex Department, Institute of Child Health, University College London, 6th Floor, Cardiac Wing, 30 Guilford Street, London, UK; e.main{at}

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

The global evolution of airway clearance techniques (ACTs) for cystic fibrosis (CF) and other respiratory disorders, with corresponding research, spans over four decades. Over this era, different ACTs have been invented, modified, retained or rejected. Some involve airway oscillation, some are independently performed and others require electricity or physical assistance. Some have strong geographical dominance, often more closely related to the origin of the technique and the strength of marketing, than to best evidence.

There has also been dramatic progress in the design, quality and rigour of research conducted to identify best practice. The best evidence from a plethora of early, underpowered, short-term studies (1–14 days in length), typically cross-over design, has been synthesised in five Cochrane reviews related to ACTs for CF, published between 2000 and 2011.1–6 All conclude that there is currently insufficient evidence to suggest superiority of any one technique. The calls for properly conducted, long-term, randomised controlled trials (RCTs) with standardised and meaningful outcome measures have intensified.

This study by McIlwaine et al answers the call elegantly.7 It is a well-designed, properly funded, long-term RCT. Results suggest that patients on high-frequency chest wall oscillation (HFCWO) therapy had more exacerbations than those on positive expiratory pressure (PEP) mask therapy, and they had them sooner. Given the substantive cost and marketing behind HFCWO (over 200 times more expensive than PEP mask therapy), these results provide important and clinically useful information that clinicians will find very helpful in making cost-effective and best practice decisions about airway clearance for their patients.7 In a landscape of ACT comparison literature, which invariably concludes that one technique or device is ‘equivalent’ to another, this is a noteworthy finding.1–6

In addition however, apart from confirming the difficulty of reaching recruitment targets, this study illuminates effectively two other challenges facing airway clearance …

View Full Text


  • Competing interests None.

  • Provenance and peer review Commissioned; internally peer reviewed.

Linked Articles