Condition category
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Prof Paul Little


Contact details

Primary Medical Care
Aldermoor Health Centre
Aldermoor Close
SO16 5ST
United Kingdom
+44 (0)23 80241062

Additional identifiers

EudraCT number number

Protocol/serial number

HTA 05/10/01

Study information

Scientific title



Study hypothesis

1. To assess which Rapid streptococcal antigen detection test (RADT) is the most accurate in predicting the presence of group A streptococcus by throat swab in a clinical sample from primary care
2. To estimate the error from sampling bias by performing parallel standardised in vitro studies
3. To assess the validity of a scoring system based on the throat swab as the reference standard (such as the Centor criteria) in a UK population
4. To assess the effectiveness and cost-effectiveness of rapid tests when compared to clinical scoring rules and delayed antibiotic prescription
5. To explore the effect of additional benefit from the RADT use on GP diagnostic prediction accuracy and treatment decisions

Ethics approval

Southampton and South West hampshire REC, MREC number: 06/Q1702/111

Study design

Randomised controlled trial

Primary study design


Secondary study design

Non randomised controlled trial

Trial setting

Not specified

Trial type


Patient information sheet

Find information pertinent to closest recruitment site at:


Lower Respiratory Tract Infections (LRTI)


This study is in two phases:
Phase I is a validation and development phase and will include five components:
1. A clinical study to determine the ease of use and overall performance in clinical settings of the 5 currently available RADTs using the throat swab as the reference standard
2. Nested data from the same sample will be used to assess whether the a scoring system based on the throat swab as a reference standard (such as the Centor criteria) requires modification
3. In vitro studies to assess the performance of RADTs in standardised conditions and thus assess the issue of sampling bias when using RADTs
4. A qualitative study to explore patients and GPs’ perceptions about the use of RADTs

Phase II. This trial will compare management using a) the best RADT defined from phase 1 compared with b) a clinical scoring rule (a Centor-like criteria based on predicting the results of throat swabs) and c) with the empirical strategy of delayed antibiotic prescription. Phase II will include a cost consequences analysis, which along with a review of the longer term effects of reduced antibiotic resistance will feed into a simple cost effectiveness model.

Phase I. RADTs: in adults two double throat swabs will be taken (allowing four tests for each adult), and in children only one double swab (due to multiple swabs being less acceptable in children). Each swab will be used for both conventional microbiology (culture and sensitivity) and for one of five randomly chosen rapid tests (piloting has shown this is feasible and minimises sampling variation). We will assess currently available RADTs (Streptatest; OSOM Ultra Strep A; Quickvue; Clearview Exact Test; and IMI Test Pack plus Strep A). Variation in performance due to sampling bias will be assessed by in vitro studies, using standard antigen loads of three group A streps and controls. The choice of RADT for phase II will take account of the best clinical study results, the in vitro results, and ease of use.

Phase II. Patients will be individually randomised using a web based service to three groups, stratified by physician belief in the likelihood of bacterial infection: 1 ) RADT use 2) Clinical scoring rule 3) Delayed prescribing. The RADT used, and the optimal strategy for use, will be identified from Phase I. The clinical score will be the Centor criteria (3 out of 4 criteria present), or the alternative clinical rule developed from phase I . Delayed prescribing will involve antibiotics to be used/collected after 3-5 days if symptoms are worsening or not starting to settle.

Intervention type



Not Specified

Drug names

Primary outcome measure

Phase 1: Ease of use and performance in clinical setting of 5 RADTs
Phase 2: Diary scores; duration of illness

Secondary outcome measures

Phase 2:
1. Antibiotic use
2. Side effects
3. Medicalistion of illness

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Phase 1: Adults/children aged 5 and over presenting with acute sore throat ( 2 weeks or less; and with some abnormality of examination of the throat – i.e. erythema and/or pus).
Phase 2: . Previously well subjects aged 3 years and over with acute illness (2 weeks or less), presenting with sore throat as the main symptom, with an abnormal examination of the pharynx.

Participant type


Age group




Target number of participants

Phase 1: 438 -1176; Phase 2: 850

Participant exclusion criteria

Phase 1:
1. Other non infective causes of sore throat (e.g. apthous ulceration, candida, drugs)
2. Unable to consent (e.g. dementia, uncontrolled psychosis)
Phase 2:
1. Quinsy, previous rheumatic fever, glomerulonephritis.
2. Serious chronic disorders where antibiotics are needed (e.g. cystic fibrosis, valvular heart disease), or mental health problems (e.g. learning difficulties - unable to complete outcome measures).

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Primary Medical Care
SO16 5ST
United Kingdom

Sponsor information


University of Southampton (UK)

Sponsor details

(c/o Dr Martina Dorward)
Research Support Office
Building 37
Room 4009
University of Southampton
SO17 1BJ
United Kingdom
+44 (0)23 80598848

Sponsor type




Funder type


Funder name

NIHR Health Technology Assessment Programme - HTA (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

2013 results in:
2014 results in:

Publication citations

  1. Results

    Little P, Hobbs FD, Moore M, Mant D, Williamson I, McNulty C, Cheng YE, Leydon G, McManus R, Kelly J, Barnett J, Glasziou P, Mullee M, , Clinical score and rapid antigen detection test to guide antibiotic use for sore throats: randomised controlled trial of PRISM (primary care streptococcal management)., BMJ, 2013, 347, f5806.

  2. Results

    Little P, Hobbs FD, Moore M, Mant D, Williamson I, McNulty C, Lasseter G, Cheng MY, Leydon G, McDermott L, Turner D, Pinedo-Villanueva R, Raftery J, Glasziou P, Mullee M, , PRImary care Streptococcal Management (PRISM) study: in vitro study, diagnostic cohorts and a pragmatic adaptive randomised controlled trial with nested qualitative study and cost-effectiveness study., Health Technol Assess, 2014, 18, 6, vii-xxv, 1-101, doi: 10.3310/hta18060.

Additional files

Editorial Notes