Who is at risk to develop glaucoma?

In this study, the people who developed glaucoma were older, had higher eye pressure, more hollowed out optic discs and thinner corneas.

People with elevated eye pressure who have not developed glaucoma may benefit from early treatment to reduce eye pressure. The benefit will depend on the person’s risk of developing glaucoma, age and other medical conditions. To find out your level of risk for developing glaucoma, speak with your eye care doctor.

The Data and Safety Monitoring Committee of OHTS, Steering Committee of OHTS and the National Eye Institute have approved a protocol modification so that all participants in OHTS will be encouraged to receive topical ocular hypotensive medication free of charge.

Additional study information

You may find more information about our study below.


Current OHTS Bibliography (pdf)

Manual of procedures

OHTS Phase 3 (pdf)

OHTS Phase 2 (pdf)

OHTS Phase 1 (pdf)

Case report forms
OHTS phase 3

Follow-up Test and Measures Visit (FV) (annotated) (pdf)
Follow-up Test and Measures for Repeat Visits (RV) (annotated) (pdf)
Symptoms Checklist (SY) (annotated) (pdf)
Visual Function Questionnaire (VQ) (annotated) (pdf)
SF-36 Quality of Life (QL) (annotated) (pdf)
Functional Measures (FM) (annotated) (pdf)
Patient Tracking Information (TR) (pdf)
Adverse Event (AE) (pdf)
Medical History Summary (annotated) (pdf)
Medical History Summary – telephone (annotated) (pdf)
ETDRS Chart 1 (pdf)
ETDRS Chart 2 (pdf)
ETDRS Chart R (pdf)
Pelli-Robson Contrast Sensitivity (PR) (pdf)
OHTS 3 ORA (annotated) (pdf)
Unable or Unwilling to Participate (pdf)
Confirmation of Death Form (DT) (pdf)
OHTS 3 Decline (pdf)

OHTS phase 1 & 2 (annotated)

Adverse Event (AE16) (pdf)
Additional Measures (AM2) (pdf)
Axial Length (AX16) (pdf)
Baseline Randomization (BR2) (pdf)
Confirmation Visit (CF10) (pdf)
Contact Verification (CV1) (pdf)
Decline to Participate-Genetics (DG16) (pdf)
Diabetes History (DH16) (pdf)
Death (DT3) (pdf)
Endpoint (EN12) (pdf)
Functional Measure (FM16) (pdf)
Follow-up Visit (FV21) (pdf)
Genetics Consent (GC3) (pdf)
IOP Determination (IP2) (pdf)
Lens Opacities Classification (LC3) (pdf)
Missed Visit (MV6) (pdf)
Protocol Exemption (PE3) (pdf)
Pachymetry (PY16) (pdf)
Qualifying Assessment (QA5) (pdf)
Quality of Life (QL16) (pdf)
Symptom Checklist (SY6) (pdf)
Treatment Change (TC11) (pdf)
Transition Visit Status (TV1) (pdf)
Unscheduled Visit (UN16) (pdf)
NEI VFQ (VQ16) (pdf)


Pre- and Post-POAG Rates of Visual Field Progression (The Association for Research in Vision and Ophthalmology 2023)
The OHTS 5-Year Risk Calculator is Applicable to Treated Patients (American Glaucoma Society 2023)
Re-Enrolling Study Participants (Society of Clinical Research Associates 2017)
Using a Professional Tracing Service (Society for Clinical Trials 2018)
Do Site Visits Improve Participant Re-Engagement? (Society for Clinical Trials 2018)

Endpoint procedures

Endpoint procedure (pdf)

Data and safety monitoring committee

The Data and Safety Monitoring Committee (DSMC) is an independent scientific committee appointed by the National Eye Institute to oversee the study and to evaluate study results. The DSMC determined that the evidence from the study showed that eyedrop medication to lower eye pressure was effective in delaying or preventing glaucoma.

The rate of developing glaucoma in OHTS was reduced by more than 50% in people using eye drop medications. In addition, there was little evidence of an increase in side effects.

At 5 years, 4.4% of the participants receiving eye drop medication developed glaucoma and 9.5% of the participants not receiving eye drop medications developed glaucoma. The risk of developing glaucoma was reduced by more than 50% among participants receiving eye drop medications.

Final progress report

 Final progress report (pdf)

PowerPoint slides

Confirmation of Visual Field Abnormalities in the Ocular Hypertension Treatment Study (OHTS) 2000.

Central Corneal Thickness in the Ocular Hypertension Treatment Study (OHTS) 2001.

OHTS Phase 1 Results 2002

Managing Patients with Ocular Hypertension. AGS 2010.

Incidence of Glaucomatous Visual Field Loss Subsequent to Glaucomatous Optic Disc Deterioration. ARVO 2010.

Impact of the Endpoint Committee on Endpoint Incidence, Treatment Efficacy and Statistical Power in the OHTS. ARVO 2011.

The 10 Year Incidence of Glaucoma Among Treated and Untreated Ocular Hypertensive Patients. ARVO 2011.

The 10 Year Incidence of Glaucoma Among Treated and Untreated Ocular Hypertensive Patients. AAO 2011.

Ocular Hypertension Treatment Study: 20-Year Incidence & Severity of Primary Open-Angle Glaucoma (POAG). AAO 2019.

Characterization of retinal nerve fiber layer and ganglion cell layer inner plexiform thickness in the Ocular Hypertension Treatment Study (OHTS 3) 20-year follow-up. International Perimetric Society, August 11, 2022, Berkley, CA.

“Ocular Hypertension Blues” Video (Chris Johnson)