Condition category
Eye Diseases
Date applied
30/09/2005
Date assigned
30/09/2005
Last edited
10/09/2008
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information

Type

Scientific

Primary contact

Prof Bruce Evans

ORCID ID

Contact details

23 Shenfield Rd
Brentwood
CM15 8AG
United Kingdom
+44 (0)1277 211164
bruce.evans@virgin.net

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

M0003074909

Study information

Scientific title

Acronym

Study hypothesis

Optometrists usually prescribe interventions (spectacles, contact lenses or orthoptics) if the intervention improves visual acuity, or if it is believed that it will resolve symptoms. For optometric interventions that are prescribed for symptomatic relief, clinical tests of visual acuity (VA) often do not indicate significant improvement with the intervention.

Visual problems which cause symptoms but do not impair static VA might affect performance on dynamic tasks. Refractive errors and heterophoria are best described as continuous variables and the decision as to when to prescribe an intervention is based on clinical signs whose sensitivity and specificity for detecting symptoms is often, at best, under researched.

The objectively validated Wilkins Rate Of Reading Test will be used to assess the benefit of interventions. This test uses simple words and is relatively independent of reading skill and does not assess linguistic or semantic factors. The results are very dependent on dynamic visual skills and require sustained binocular single vision and clear vision.

The aims of the research
1. In conditions where optical corrections may be prescribed but not improve VA (e.g. decompensated heterophoria): to investigate whether optical corrections influence performance at the Wilkins Rate of Reading test.

2. In conditions where optical corrections may be prescribed and improve VA (e.g. astigmatism): to investigate whether optical corrections influence performance at the Wilkins Rate of Reading test.

3. In both (1) and (2), to investigate the relationship between the severity of the optometric anomalies and the magnitude of any improvement in the Rate of Reading.

4. If the Wilkins Rate of Reading Test does prove to be a useful tool for exploring any benefit from the ¿borderline¿ optometric interventions, to investigate the inter-relationships between the Wilkins Rate of Reading Test result, symptoms and conventional clinical test results.

Ethics approval

Not provided at time of registration

Study design

Randomised controlled trial

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type

Not Specified

Patient information sheet

Condition

Eye Diseases: Vision disorders

Intervention

Subjects will be invited to return on the research day. They will then be tested four times with the rate of reading test, twice with the appropriate intervention A and twice with the control lens (B). The order of testing will be ABBA or BAAB (randomly) to control for practice effects. The interventions and controls for the five groups identified are summarised.

Hypermetropes will be tested with subjective refractive correction (A) and size lenses to give similar magnification (B)

Astigmats will be tested with subjective cylindrical correction (A) and best vision sphere (B)

Horizontal heterophorias will be tested with aligning prism from Mallett unit (A) and size lenses for exophoria or plano for esophoria as appropriate (B)

Vertical heterophorias will be tested with larger of aligning prism/dissociated heterophoria (A) and plano trial lenses (B)

Early presbyopes will be tested with near refractive correction (A) and size lenses (B).

Clinical data will be obtained using standard testing protocols on all subjects, and a selection from VA, cover test, foveal suppression, dissociated heterophoria, fusional reserves, Randot circles, fixation disparity. Detailed symptom questionnaires designed for each group will be used.
Subjects will be assessed from patients routinely attending the practice for eye examinations.

Intervention type

Other

Phase

Not Specified

Drug names

Primary outcome measures

Process measure: does prescribing optometric correction for marginal refractive and orthoptic anomalies benefit patients in terms of improved performance on the Wilkins Rate of Reading test?

Secondary outcome measures

Not provided at time of registration

Overall trial start date

01/07/1998

Overall trial end date

31/03/2008

Reason abandoned

Eligibility

Participant inclusion criteria

Subjects meeting the following criteria will be selected, regardless of whether they have any existing refractive correction. All subjects meeting the criteria will be invited to participate.
1. Hypermetropes of age <40years with either retinoscopy or subjective refraction in the better eye in the range +0.75 to +1.50D
2. Patients aged 40-45 years with a subjective near correction in the range +0.50 to +1.50D
3. Astigmats of any age with astigmatism (subjectively) in the better eye in the range 0.50 to 1.50DC
4. Patients of any age with horizontal heterophoria that may be decompensated
5. Patients of any age with a vertical heterophoria either on the Mallett unit or dissociation test of >0.5^

Participant type

Patient

Age group

Adult

Gender

Not Specified

Target number of participants

Not provided at time of registration

Participant exclusion criteria

No specific patient exclusion criteria

Recruitment start date

01/07/1998

Recruitment end date

31/03/2008

Locations

Countries of recruitment

United Kingdom

Trial participating centre

23 Shenfield Rd
Brentwood
CM15 8AG
United Kingdom

Sponsor information

Organisation

Department of Health

Sponsor details

Richmond House
79 Whitehall
London
SW1A 2NL
United Kingdom
+44 (0)20 7307 2622
dhmail@doh.gsi.org.uk

Sponsor type

Government

Website

http://www.dh.gov.uk/Home/fs/en

Funders

Funder type

Government

Funder name

City Eye Clinic (EYENET) (UK), NHS R&D Support Funding

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

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

Results - basic reporting

Publication summary

2006 results on http://www.ncbi.nlm.nih.gov/pubmed/17040419

Publication citations

  1. Results

    O'Leary CI, Evans BJ, Double-masked randomised placebo-controlled trial of the effect of prismatic corrections on rate of reading and the relationship with symptoms., Ophthalmic Physiol Opt, 2006, 26, 6, 555-565, doi: 10.1111/j.1475-1313.2006.00400.x.

Additional files

Editorial Notes