Condition category
Eye Diseases
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Cataracts are cloudy areas on the lens of the eye. They can appear for a number of reasons however they are most common in older people, developing over a long period of time (senile cataract). The lens sits near the front of the eye, and plays an important role in vision. When cataracts cause the lens to become clouded, it can prevent light from reaching the back of the eye (retina) to form an image that can be interpreted by the brain. When this happens, vision becomes blurred and distorted, and can eventually lead to blindness. In many cases, the only effective treatment is to undergo cataract surgery, which involves removing the affected lens and replacing it with a clear artificial one (intraocular lens). Un-operated cataract remains the leading cause of blindness in China, and China’s cataract surgical rate (CSR) of 1000/million/year is lower than that of neighboring countries such as Vietnam (2000) and India (5500). This problem is particularly bad in rural (countryside) areas. The aim of this study is to investigate the socioeconomic (social and financial) impact of receiving free cataract surgery.

Who can participate?
Adults aged 40 years and over living in Handan County, China with poor vision in one eye due to cataracts that have not been operated on.

What does the study involve?
Participants are randomly allocated to one of two groups. Those in the first group receive cataract surgery immediately. Those in the second group are placed on a waiting list to receive cataract surgery a year later. At the start of the study and then after one year, participants in both groups complete a number of questionnaires designed to measure their household income, whether they are working and their wellbeing.

What are the possible benefits and risks of participating?
Participants who receive the surgery immediately will benefit from an improved ability to see clearly. There are no notable risks involved with participating other than the general risks of undergoing eye surgery.

Where is the study run from?
Shaanxi Normal University (China)

When is the study starting and how long is it expected to run for?
September 2016 to January 2018

Who is funding the study?
Stanford University (USA)

Who is the main contact?
Mr Matthew Boswell

Trial website

Contact information



Primary contact

Mr Matthew Boswell


Contact details

Stanford University
Encina Hall E501
616 Serra Street
United States of America

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Socioeconomic Impact of Cataract Surgery for Elderly Patients in China: Results from a Randomized Trial


Handan Cataracts Study

Study hypothesis

The aim of this study is to measure the impact of cataract surgery on key household socioeconomic outcomes such as income and labor market participation.

Ethics approval

Not provided at time of registration

Study design

Randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type

Quality of life

Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet




Participants are randomised to one of two groups based on baseline characteristics.

Intervention group: Participants undergo cataract surgery in February 2017. This involves small incision manual cataract surgery performed by an experienced surgeon with insertion of an appropriate intra-ocular lens, power to be determined in standard fashion by measurement of corneal curvature, axial length and refractive power in the operative and non-operative eyes.

Control group: Participants are placed on a wait-list and receive their cataract surgery in February 2018 after the collection of the final outcome measures.

Participants in both groups are followed up in standard fashion by an ophthalmologist from Tongren Hospital and complete follow up surveys after one year.

Intervention type


Drug names

Primary outcome measure

1. Household income is measured using the Handan Cataract Study Household Socioeconomic Survey at baseline and 12 months
2. Household member time allocation is measured using the Handan Cataract Study Household Socioeconomic Survey at baseline and 12 months
3. Household member labor market participation is measured using the Handan Cataract Study Household Socioeconomic Survey at baseline and 12 months

Secondary outcome measures

1. Household member educational outcomes are measured using the Handan Cataract Study Household Socioeconomic Survey at baseline and 12 months
2. Household member subjective wellbeing is measured using the Handan Cataract Study Household Socioeconomic Survey at baseline and 12 months

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. LogMAR vision ≥ 0.5 in the better-seeing eye due to un- operated cataract identified in the original Handan Eye Study (2012)
2. Resident of Handan County, China
3. Aged 40 years and over

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Unwilling to give consent or unable to be contacted
2. Other ocular or health conditions that contraindicate or prevent the patient from undergoing cataract surgery

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Shaanxi Normal University

Sponsor information


Stanford University

Sponsor details

450 Serra Mall
United States of America

Sponsor type




Funder type


Funder name

Stanford University

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Planned publication in one or more high-impact peer reviewed journals prior to one year following the conclusion of the trial.

IPD Sharing plan:
The datasets generated during and/or analysed during the current study are/will be available upon request from Matthew Boswell (

Intention to publish date


Participant level data

Available on request

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes