A multicentre, randomised controlled trial to compare the clinical and cost-effectiveness of Lee Silverman Voice Treatment versus standard NHS Speech and Language Therapy versus control in Parkinson's disease: a study protocol for a randomised controlled trial

BACKGROUND

Parkinson's disease (PD) affects approximately 145,519 people in the UK. Speech impairments are common with a reported prevalence of 68%, which increase physical and mental demands during conversation, reliance on family and/or carers, and the likelihood of social withdrawal reducing quality of life. In the UK, two approaches to Speech and Language Therapy (SLT) intervention are commonly available: National Health Service (NHS) SLT or Lee Silverman Voice Treatment (LSVT LOUD®). NHS SLT is tailored to the individuals' needs per local practice typically consisting of six to eight weekly sessions; LSVT LOUD® comprises 16 sessions of individual treatment with home-based practice over 4 weeks. The evidence-base for their effectiveness is inconclusive.

METHODS/DESIGN

PD COMM is a phase III, multicentre, three-arm, unblinded, randomised controlled trial. Five hundred and forty-six people with idiopathic PD, reporting speech or voice problems will be enrolled. We will exclude those with a diagnosis of dementia, laryngeal pathology or those who have received SLT for speech problems in the previous 2 years. Following informed consent and completion of baseline assessments, participants will be randomised in a 1:1:1 ratio to no-intervention control, NHS SLT or LSVT LOUD® via a central computer-generated programme, using a minimisation procedure with a random element, to ensure allocation concealment. Participants randomised to the intervention groups will start treatment within 4 (NHS SLT) or 7 (LSVT LOUD®) weeks of randomisation.

PRIMARY OUTCOME

Voice Handicap Index (VHI) total score at 3 months. Secondary outcomes include: VHI subscales, Parkinson's Disease Questionnaire-39; Questionnaire on Acquired Speech Disorders; EuroQol-5D-5 L; ICECAP-O; resource utilisation; adverse events and carer quality of life. Mixed-methods process and health economic evaluations will take place alongside the trial. Assessments will be completed before randomisation and at 3, 6 and 12 months after randomisation. The trial started in December 2015 and will run for 77 months. Recruitment will take place in approximately 42 sites around the UK.

DISCUSSION

The trial will test the hypothesis that SLT is effective for the treatment of speech or voice problems in people with PD compared to no SLT. It will further test whether NHS SLT or LSVT LOUD® provide greater benefit and determine the cost-effectiveness of both interventions.

TRIAL REGISTRATION

International Standard Randomised Controlled Trials Number (ISRCTN) Registry, ID: 12421382. Registered on 18 April 2016.

The generation of consensus guidelines for carrying out process evaluations in rehabilitation research

BACKGROUND

Although in recent years there has been a strong increase in published research on theories (e.g. realist evaluation, normalization process theory) driving and guiding process evaluations of complex interventions, there is limited guidance to help rehabilitation researchers design and carry out process evaluations. This can lead to the risk of process evaluations being unsystematic. This paper reports on the development of new consensus guidelines that address the specific challenges of conducting process evaluations alongside clinical trials of rehabilitation interventions.

METHODS

A formal consensus process was carried out based on a modified nominal group technique, which comprised two phases. Phase I was informed by the findings of a systematic review, and included a nominal group meeting with an expert panel of participants to rate and discuss the proposed statements. Phase II was an in depth semi-structured telephone interviews with expert panel participants in order to further discuss the structure and contents of the revised guidelines. Frequency of rating responses to each statement was calculated and thematic analysis was carried out on all qualitative data.

RESULTS

The guidelines for carrying out process evaluations within complex intervention rehabilitation research were produced by combining findings from Phase I and Phase II. The consensus guidelines include recommendations that are grouped in seven sections. These sections are theoretical work, design and methods, context, recruitment and retention, intervention staff, delivery of the intervention and results. These sections represent different aspects or stages of the evaluation process.

CONCLUSION

The consensus guidelines here presented can play a role at assisting rehabilitation researchers at the time of designing and conducting process evaluations alongside trials of complex interventions. The guidelines break new ground in terms of concepts and theory and works towards a consensus in regards to how rehabilitation researchers should go about carrying out process evaluations and how this evaluation should be linked into the proposed trials. These guidelines may be used, adapted and tested by rehabilitation researchers depending on the research stage or study design (e.g. feasibility trial, pilot trial, etc.).