Glaucoma Detection Study data, KCMC, Tanzania – Data Codebook

Persistent Identifier

10.17037/DATA.00005260

Description

The aim of the Glaucoma Detection Study (GDS) was to develop and evaluate a low-cost, portable, and easy-to-use detection system for glaucoma, the leading irreversible cause of blindness worldwide. This assessed a combination of three diagnostic tests to identify glaucoma: (1) Eyecatcher visual field testing, a tablet- or laptop-based eye-tracking system that measures visual field loss; (2) PEEK Contrast Sensitivity testing, a smartphone-based assessment of visual function; and (3) optic disc photography using a portable Remidio fundus camera to capture images of the optic nerve. Participants enrolled on the study possessed different levels of glaucoma condition, from healthy individuals with no glaucoma to patients with advanced glaucoma, who were recruited at ophthalmology outpatient clinics at the Kilimanjaro Christian Medical Centre (KCMC) in Tanzania. Data from a parallel UK study were also analysed in the study. The dataset contains measurements recorded during this investigation, such as visual acuity (VA), intraocular pressure (IOP), anterior chamber angle grading, perimetry parameters (e.g. mean deviation, MD), as well as novel investigation details including eye-movement perimetry (Eyecatcher) hit rate or score, Remidio fundus camera artificial intelligence grading, and clinician assessment of Remidio fundus photographs (e.g. disc damage likelihood score, DDLS, cup:disc ratio, CDR).

Data Codebook

The dataset contains 83 variables outlined below.

Variable Name Variable Label Answer Label Answer Code Variable Type
eye Eye being assessed (Right/Left)     Categorical
    Left L  
    Right R  
eyeEnrolled Whether eye was enrolled in study     Binary
    No 0  
    Yes 1  
eyesEnrolled Number/which eyes enrolled     Categorical
    Both B  
    Left L  
    Right R  
diagnosisGlaucoma Glaucoma diagnosis status     String
    No glaucoma No glaucoma  
    POAS - Primary Open-Angle Glaucoma Suspect POAS - Primary Open-Angle Glaucoma Suspect  
    POAG - Primary High Pressure Open-Angle Glaucoma POAG - Primary High Pressure Open-Angle Glaucoma  
    PACS - Primary Chronic Angle-Closure Glaucoma Suspect PACS - Primary Chronic Angle-Closure Glaucoma Suspect  
    PACG - Primary Chronic Angle-Closure Glaucoma PACG - Primary Chronic Angle-Closure Glaucoma  
    PAC - Primary Chronic Angle-Closure PAC - Primary Chronic Angle-Closure  
    OHT - Ocular Hypertension OHT - Ocular Hypertension  
diagnosisOther Other ophthalmic diagnosis     String
    Diabetic Retinopathy Diabetic Retinopathy  
    Senile Cataract Senile Cataract  
    diagnosisOther diagnosisOther  
vaPlainPeekSn Presenting visual acuity (Snellen value)   Open ended Numeric
vaPinholePeekSn Pinhole visual acuity (Snellen value)   Open ended Numeric
vaGlassesPeekSn Visual acuity with glasses (Snellen value)   Open ended Numeric
plPeekLM Presenting VA in logMAR   Open ended Numeric
pinPeekLM Pinhole VA in logMAR   Open ended Numeric
glPeekLM Glasses-corrected VA in logMAR   Open ended Numeric
bestVApeekLM Best visual acuity in logMAR - Best of measured values   Numeric
contrastSensitivityNum Contrast sensitivity score   0.00-2.25 log units Numeric
contrastSensitivityMenu Contrast sensitivity category (Study-defined categories)   Categorical
      Not examined / not asked  
      Not documented  
contrastBrightnessNum Contrast brightness value   Device output Numeric
contrastBrightnessTxt Brightness category/label     String
    lx lx  
ecCompleted Eyecatcher visual field completed     String
    No No  
    Yes Yes  
ecReasonNotCompleted Reason Eyecatcher not completed     Categorical
    Calibration not working Calibration not working  
    Not applicable Not applicable  
    Other (specify in comments) Other (specify in comments)  
eyecatcherReasonNotComplComment Comments on non-completion   Open ended String
eyecatcherReasonNotComplText Reason not completed (text)   Open ended String
ecRepeatCompleted Repeat Eyecatcher completed     String
    No No  
    Yes Yes  
remidioCompleted Remidio optic disc photography completed     String
    No No  
    Yes Yes  
remidioCompletedComment Comments on Remidio test   Open ended String
dilatedFundusImage Dilated fundus image obtained     String
    No No  
    Yes Yes  
dilatedFundusImageComment Comments on image acquisition   Open ended String
    not applicable NA  
fixationLosses HVF fixation losses (count)   Open ended Numeric
falsePosErr HVF false positive errors (count)   Open ended Numeric
falseNegErr HVF false negative errors (count)   Open ended Numeric
durationMin HVF test duration - minutes   Open ended Numeric
durationSec HVF test duration - seconds   Open ended Numeric
strategy HVF strategy     Categorical
    SITA-standard SITA-standard  
    strategy strategy  
GHT Glaucoma Hemifield Test result     Categorical
    within normal limits within normal limits  
    outside normal limits outside normal limits  
    borderline borderline  
    general depression of sensitivity general depression of sensitivity  
    abnormal high sensitivity abnormal high sensitivity  
VFI Visual Field Index (0-100%)   Open ended Numeric
MDdB Mean Deviation (dB)   Open ended Numeric
MDp Mean Deviation probability value (p-value)   Open ended Numeric
PSDdB Pattern Standard Deviation (dB)   Open ended Numeric
PSDp PSD p-value   Open ended Numeric
ecEasy Eyecatcher easy to perform response     Ordinal
    1 - Strongly disagree - Sikubaliani kabisa 1  
    2 - Disagree - Sikubaliana 2  
    3 - Neither agree nor disagree - Kwa wastani 3  
    4 - Agree - Nakubaliana 4  
    5 - Strongly agree - Nakubaliana sana 5  
ecEasierThanHFA Eyecatcher easier than Humphrey VF     Ordinal
    1 - Strongly disagree - Sikubaliani kabisa 1  
    2 - Disagree - Sikubaliana 2  
    3 - Neither agree nor disagree - Kwa wastani 3  
    4 - Agree - Nakubaliana 4  
    5 - Strongly agree - Nakubaliana sana 5  
hfaEasierThanEC Humphrey VF easier than Eyecatcher     Ordinal
    1 - Strongly disagree - Sikubaliani kabisa 1  
    2 - Disagree - Sikubaliana 2  
    3 - Neither agree nor disagree - Kwa wastani 3  
    4 - Agree - Nakubaliana 4  
    5 - Strongly agree - Nakubaliana sana 5  
eyecatcherVsHFAcomment Comments comparing tests   Open ended String
iopA Intraocular pressure reading A (mmHg)     Numeric
iopAmethod Method used for IOP A     Categorical
    iCare tonometry iCare tonometry  
    Applanation tonometry Applanation tonometry  
    Slitlamp examination Slitlamp examination  
iopB Intraocular pressure reading B (mmHg)   Open ended Numeric
iopBmethod Method used for IOP B     Categorical
      Applanation tonometry  
      iCare tonometry  
      iopBmethod  
iopC Intraocular pressure reading C (mmHg)     Numeric
iopCmethod Method used for IOP C     Categorical
    Applanation tonometry Applanation tonometry  
    iCare tonometry iCare tonometry  
    iopCmethod iopCmethod  
WHOcatNUC WHO nuclear cataract category (WHO grading)   Open ended Ordinal
WHOcatCOR WHO cortical cataract category (WHO grading)   Open ended Ordinal
WHOcatPSC Applanation, iCare, etc. (WHO grading)   Open ended Ordinal
pseudophYN Pseudophakia present     binary
    Yes Yes  
    No No  
    Not examined / not asked Not examined / not asked  
    Not documented Not documented  
vanHerickNum Van Herick grade numeric     Numeric
    Not documented Not documented  
vanHerickDropdown Van Herick category     Categorical
    Not documented Not documented  
vanHerickText Van Herick description - Extent of narrowing   Open ended String
vanHerickComment Comments on angle assessment   Open ended String
CDrVer Vertical cup-disc ratio   0-1 Numeric
DDLS Disc Damage Likelihood Scale (DDLS score)   Open ended ordinal
discHaemclin Clinical disc haemorrhage present     String
    No No  
    Yes Yes  
discHaemcomment Disc haemorrhage comments     String
    not applicable NA  
rimNotch Neuroretinal rim notch present     String
    No No  
    Yes Yes  
rimNotchcomment Rim notch comments   Open ended String
othersONH Other optic nerve head findings   Open ended String
shafferInf Shaffer grade inferior angle   0-4 Ordinal
shafferInfComm Inferior angle comments     String
    not applicable NA  
shafferSup Shaffer grade superior angle   0-4 Ordinal
shafferSupComm Superior angle comments     String
    not applicable NA  
shafferNas Shaffer grade nasal angle   0-4 ordinal
shafferNasComm Nasal angle comments     String
    not applicable NA  
shafferTemp Shaffer grade temporal angle   0-4 ordinal
shafferTempComm Temporal angle comments     String
    not applicable NA  
remidioCompleted Remidio grading completed     String
    No No  
    Yes Yes  
QualityOfThePhotoIfGradeable Photo quality grade     String
    Excellent excellent  
    Moderate moderate  
    Poor poor  
    Ungradable ungradable  
CDrVerVH Vertical cup-disc ratio from image grading   0-1 Numeric
DDLSVH DDLS from image grading (DDLS score)     ordinal
    not applicable NA  
cdrmed Cup-disc ratio from Medios   0-1 Numeric
    Ungradable ungradable  
    No image No image  
    Participant record not found Participant record not found  
Medios_refer Referral recommendation from Medios     String
    No referral no  
    Insufficient insufficient  
    Immediate referral immediately  
    Refer (disc suspect) refer (disc suspect)  
    Refer (image missing for at least 1 eye) refer (image missing for at least 1 eye)  
Medios_refer2 Referral recommendation from Medios   0-5 Ordinal
Medios_quality Media/image quality assessment from Medios     String
    Good good  
    Insufficient insufficient  
discHaem Disc haemorrhage on image grading     binary
    No no  
    Yes yes  
rimNotch_focal_thinning Focal rim thinning/notch     binary
    No no  
    Yes yes  
comment General comments on Medios image   Open ended String
Refer_for_non_glaucoma_reason Referral for non-glaucoma pathology     binary
    No no  
    Yes yes  
Notes_on_non_glaucoma_referral Referral notes   Open ended String