FUNDUS PHOTOGRAPHY A photograph of the ocular fundus of one eye was taken on examinees aged 40 years and over by a trained examiner in the mobile examination center (MEC). The protocol for this component did not detail any medical, safety or other exclusions. However, if the designated eye was unavailable due to an extremely small pupil, severe corneal or lens opacity, complete retinal detachment, or other reason, the other eye was photographed. If both eyes were unavailable, no photograph was taken. Because the component was administered in the examination center, MEC examination weights (WTPFEX6) should be used for data analysis. For more information on the use of sample weights in the analysis of NHANES III data, refer to the NHANES III Analytic and Reporting Guidelines (U.S. DHHS, 1996b). Photographs of the ocular fundus were taken to determine the presence of diabetic retinopathy, age-related maculopathy, and other retinal diseases that are the leading causes of vision loss in the United States. A non-stereoscopic, color, 45-degree photograph, centered between the optic nerve and the macula, was taken of one randomly selected eye. The camera used was a Canon CR4-45NM "non-mydriatic" fundus camera, which incorporated the use of an infrared video camera to allow photographs to be taken in a darkened examination room without the use of dilating drops. In a darkened room, the sphincter muscle of the iris normally relaxes, allowing for dilation of the pupil, usually to 6-10 mm in diameter. The technician observed the eye's natural dilation on a special video monitor and took the color photograph with a single flash of white light. If the examinee wore a contact lens, the photograph was taken directly through the contact lens. The entire procedure usually took less than six minutes. Detailed information on the examination procedure is in the Fundus Photography chapter of the Health Technician's Manual (U.S. DHHS, 1996b). The exposed film was mailed to the University of Wisconsin-Madison, Department of Ophthalmology, where it was processed by a local laboratory into transparencies that were evaluated for photographic quality. The ocular fundus images on the final transparencies were reviewed by photograph graders to assess the presence of diabetic retinopathy, age-related maculopathy, and other retinal diseases. The grading system used for classifying diabetic retinopathy was based on a modification of the Airlie House Classification Scheme (Diabetic Retinopathy Study Group, 1981; Klein, 1984; Klein, 1986; The Early Treatment Diabetic Retinopathy Study Group, 1991). The Modified Airlie House Classification of Diabetic Retinopathy slide standards consist of 27 stereo pairs of color fundus photographs of diabetic retinopathy and one slide depicting poor photographic quality. The standard slides show diabetic proliferative disease and are used for grading the severity of diabetic retinopathy. The set is available with a detailed chapter outlining its use and a sample grading form. Additional information is available from The Fundus Photograph Reading Center, c/o Michael Neider, WARF Building Room 450, 610 Walnut Street, Madison, WI 53705. The fundus photography consultant provided extensive training to technicians at their time of hire, and each technician's performance was monitored in the field on a periodic basis. Two sources of nonsampling or measurement error were monitored throughout the survey, the picture taking procedure and the image grading procedure. To ensure that adequate photographs were taken, the technicians' performance was monitored by a review of photographs at the University of Wisconsin and by review and retraining field visits. To evaluate the grading procedure, 1500 transparencies were chosen at random for use in assessing inter- and intra-grader reliability. The Kappa statistic was chosen to assess agreement (Fleiss, 1981). The measures of agreement were generally good to excellent and improved across time. Data processing and editing were performed to ensure internal data consistency. Notes have been provided for variables requiring additional explanation. NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ INTRODUCTORY INFORMATION AND CONDITIONS AFFECTING RESULTS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6000 Photo taken? See note FPPPHOTO 9239 1 Yes 209 2 No 289 8 Blank but applicable 21574 Blank 6001 Eye color: right eye FPP1A 1995 1 Blue 1567 2 Other 5301 3 Brown 874 8 Blank but applicable 21574 Blank 6002 Eye color: left eye FPP1B 1991 1 Blue 1572 2 Other 5300 3 Brown 874 8 Blank but applicable 21574 Blank 6003-6004 Pupil size before dilation in normal FPP2 room light (mm) 9102 00-10 635 88 Blank but applicable 21574 Blank 6005-6006 Pupil size during photography as FPP3 measured on camera monitor (mm) 9058 00-12 679 88 Blank but applicable 21574 Blank 6007-6008 Elapsed time between darkening room and FPP4MIN taking photograph (min) 9059 00-50 678 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ INTRODUCTORY INFORMATION AND CONDITIONS AFFECTING RESULTS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6009-6010 Elapsed time between darkening room and FPP4SEC taking photograph (sec) 9057 00-59 680 88 Blank but applicable 21574 Blank 6011-6015 Photographer FPPPHTG 9456 01001-09018 281 88888 Blank but applicable 21574 Blank 6016 Eye FPPEYE 4436 1 Right 4470 2 Left 831 8 Blank but applicable 21574 Blank 6017-6019 Grader code FPP1005 4209 016 1st grader 4864 102 2nd grader 664 888 Blank but applicable 21574 Blank 6020-6021 Fundus See note FPP1020 163 00 Absent (End) 8910 02 Present 664 88 Blank but applicable 21574 Blank 6022-6023 Focus FPP1030 6721 00 Good/fair 1235 01 Borderline (can't grade small microaneurysms or drusen) 954 02 Poor 827 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ INTRODUCTORY INFORMATION AND CONDITIONS AFFECTING RESULTS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6024-6025 Field definition FPP1041 6418 00 Good 2228 01 Fair 206 02 Poor 58 08 Can't grade 827 88 Blank but applicable 21574 Blank 6026-6027 Horizontal field definition FPP1046 7040 00 Good 514 01 Temporal 1295 02 Nasal 61 08 Can't grade 827 88 Blank but applicable 21574 Blank 6028-6029 Vertical field definition FPP1047 7529 00 Good 1108 01 High 197 02 Low 76 08 Can't grade 827 88 Blank but applicable 21574 Blank 6030-6031 Artifact present FPP1050 2035 00 None 6875 02 Yes 827 88 Blank but applicable 21574 Blank 6032-6033 Type of artifact: haze FPP1051 3756 00 None 5154 02 Yes 827 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ INTRODUCTORY INFORMATION AND CONDITIONS AFFECTING RESULTS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6034-6035 Type of artifact: dust/dirt FPP1052 7291 00 None 1619 02 Yes 827 88 Blank but applicable 21574 Blank 6036-6037 Type of artifact: lashes FPP1053 8328 00 None 582 02 Yes 827 88 Blank but applicable 21574 Blank 6038-6039 Type of artifact: arc FPP1054 8477 00 None 433 02 Yes 827 88 Blank but applicable 21574 Blank 6040-6041 Type of artifact: uneven illumination, FPP1055 center 7950 00 None 960 02 Yes 827 88 Blank but applicable 21574 Blank 6042-6043 Type of artifact: uneven illumination, FPP1056 edge 8497 00 None 413 02 Yes 827 88 Blank but applicable 21574 Blank 6044-6045 Type of artifact: central dot FPP1057 6545 00 None 2365 02 Yes 827 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ INTRODUCTORY INFORMATION AND CONDITIONS AFFECTING RESULTS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6046-6047 Type of artifact: other FPP1059 8638 00 None 272 02 Yes 827 88 Blank but applicable 21574 Blank 6048-6049 Gradability See note FPP1060 7298 00 Entire field gradable 30 01 Disc ungradable 764 02 Portion of macula ungradable 357 03 Macula ungradable 77 04 Portion of disc/macula ungradable 77 05 Disc and macula ungradable 307 06 Entire field ungradable (End) 827 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6050-6052 Diabetic retinopathy level See note FPP1070 7523 010 No retinopathy 93 011 Questionable retinopathy 55 012 Non-diabetic retinopathy 30 014 Hard exudates, soft exudates, intraretinal microvascular abnormalities (IRMA), without microaneurysms 66 015 Hemorrhages only, no microaneurysms 219 020 Microaneurysms only 113 031 Early non-proliferative diabetic retinopathy 82 041 Moderate non-proliferative diabetic retinopathy 14 051 Severe non-proliferative diabetic retinopathy 5 060 Fibrous proliferation only 5 065 Proliferative diabetic retinopathy (PDR) less than diabetic retinopathy standards (DRS) high risk characteristics (HRC) for severe visual loss 3 070 PDR greater than or equal to DRS HRC for severe visual loss 395 088 Can't grade 1134 888 Blank but applicable 21574 Blank 6053-6054 Hemorrhages or microaneurysms FPP1080 7579 00 None 92 01 Questionable 521 02 Less than DRS 2A 18 03 Greater than or equal to DRS 2A 393 08 Can't grade 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6055-6056 Hard exudates FPP1090 8055 00 None 38 01 Questionable 61 02 Less than DRS 3 99 03 Greater than or equal to DRS 3 350 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6057-6058 Soft exudates FPP1100 8180 00 None 36 01 Questionable 118 02 Present 269 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6059-6060 Intraretinal microvascular abnormalities FPP1110 (IRMA) 8107 00 None 37 01 Questionable 43 02 Present 416 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6061-6062 Venous beading FPP1120 8345 00 None 8 01 Questionable 5 02 Present 245 08 Can't grade 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6063-6064 New vessels in disc FPP1130 8463 00 None 7 01 Questionable 1 02 Less than DRS 10A 2 03 Greater than or equal to DRS 10A 130 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6065-6066 New vessels elsewhere FPP1140 8423 00 None 6 01 Questionable 4 02 Less than 1/2 disc area 1 03 Greater than or equal to 1/2 disc area 169 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6067-6068 Fibrous proliferation FPP1150 8482 00 None 6 01 Questionable 6 02 Fibrous proliferation elsewhere (FPE) only 1 03 Fibrous proliferation disc (FPD) only 3 04 FPE and FPD 105 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6069-6070 Pre-retinal hemorrhage or vitreous FPP1160 hemorrhage 8498 00 None 3 01 Questionable 1 02 Preretinal hemorrhage (PRH) only 1 03 Vitreous hemorrhage (VH) only 100 08 Can't grade 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6071-6072 Other abnormalities FPP1170 6266 00 No 2337 02 Yes 1134 88 Blank but applicable 21574 Blank 6073-6074 Degeneration of retinal pigment FPP1172 epithelium (RPE) 8321 00 None 138 01 Questionable 144 02 Yes 1134 88 Blank but applicable 21574 Blank 6075-6076 Central circle RPE degeneration FPP1173 8485 00 None 118 02 Yes 1134 88 Blank but applicable 21574 Blank 6077-6078 Geographic atrophy FPP1174 8563 00 None 8 01 Questionable 32 02 Yes 1134 88 Blank but applicable 21574 Blank 6079-6080 Central circle geographic atrophy FPP1175 8576 00 None 27 02 Yes 1134 88 Blank but applicable 21574 Blank 6081-6082 Sub-retinal hemorrhage FPP1176 8592 00 None 3 01 Questionable 8 02 Yes 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6083-6084 Central circle sub-retinal hemorrhage FPP1177 8600 00 None 3 02 Yes 1134 88 Blank but applicable 21574 Blank 6085-6086 Sub-retinal fibrous scar FPP1178 8579 00 None 3 01 Questionable 21 02 Yes 1134 88 Blank but applicable 21574 Blank 6087-6088 Central circle sub-retinal fibrous scar FPP1179 8584 00 None 19 02 Yes 1134 88 Blank but applicable 21574 Blank 6089-6090 Sensory serous (sub-retinal) detachment FPP1180 8573 00 None 19 01 Questionable 11 02 Yes 1134 88 Blank but applicable 21574 Blank 6091-6092 Central circle sensory serous (sub- FPP1181 retinal) detachment 8594 00 None 9 02 Yes 1134 88 Blank but applicable 21574 Blank 6093-6094 Hyperpigmentation FPP1182 8360 00 None 58 01 Questionable 185 02 Yes 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6095-6096 Central circle hyperpigmentation FPP1183 8463 00 None 140 02 Yes 1134 88 Blank but applicable 21574 Blank 6097-6098 Chorioretinal abnormalities, other FPP1184 8542 00 None 7 01 Questionable 54 02 Yes 1134 88 Blank but applicable 21574 Blank 6099-6100 Central circle chorioretinal FPP1185 abnormalities, other 8575 00 None 28 02 Yes 1134 88 Blank but applicable 21574 Blank 6101-6102 Peripapillary atrophy FPP1186 8196 00 None 91 01 Questionable 316 02 Yes 1134 88 Blank but applicable 21574 Blank 6103-6104 Branch or central artery occlusion FPP1188 8598 00 None 2 01 Questionable 3 02 Yes 1134 88 Blank but applicable 21574 Blank 6105-6106 Central circle branch or central artery FPP1189 occlusion 8602 00 None 1 02 Yes 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6107-6108 Branch vein occlusion FPP1190 8560 00 None 19 01 Questionable 24 02 Yes 1134 88 Blank but applicable 21574 Blank 6109-6110 Central circle branch vein occlusion FPP1191 8600 00 None 3 02 Yes 1134 88 Blank but applicable 21574 Blank 6111-6112 Central vein occlusion FPP1192 8600 00 None 3 02 Yes 1134 88 Blank but applicable 21574 Blank 6113-6114 Central circle central vein occlusion FPP1193 8601 00 None 2 02 Yes 1134 88 Blank but applicable 21574 Blank 6115-6116 Significant arterio-venous nicking FPP1194 8536 00 None 36 01 Questionable 31 02 Yes 1134 88 Blank but applicable 21574 Blank 6117-6118 Hollenhorst plaque FPP1196 8588 00 None 9 01 Questionable 6 02 Yes 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6119-6120 Central circle Hollenhorst plaque FPP1197 8603 00 None 1134 88 Blank but applicable 21574 Blank 6121-6122 Asteroid hyalosis FPP1198 8559 00 None 5 01 Questionable 39 02 Yes 1134 88 Blank but applicable 21574 Blank 6123-6124 Central circle asteroid hyalosis FPP1199 8579 00 None 24 02 Yes 1134 88 Blank but applicable 21574 Blank 6125-6126 Nevus FPP1200 8469 00 None 54 01 Questionable 80 02 Yes 1134 88 Blank but applicable 21574 Blank 6127-6128 Central circle nevus FPP1201 8595 00 None 8 02 Yes 1134 88 Blank but applicable 21574 Blank 6129-6130 Surface wrinkling retinopathy FPP1202 8017 00 None 165 01 Questionable 421 02 Yes 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6131-6132 Central circle surface wrinkling FPP1203 retinopathy 8466 00 None 137 02 Yes 1134 88 Blank but applicable 21574 Blank 6133-6134 Abnormal disc FPP1204 8568 00 None 18 01 Questionable 17 02 Yes 1134 88 Blank but applicable 21574 Blank 6135-6136 Large cup-to-disc ratio FPP1205 8078 00 None 333 01 Questionable 192 02 Yes 1134 88 Blank but applicable 21574 Blank 6137-6138 Histoplasmosis (POHS) FPP1206 8596 00 None 2 01 Questionable 5 02 Yes 1134 88 Blank but applicable 21574 Blank 6139-6140 Central circle histoplasmosis (POHS) FPP1207 8601 00 None 2 02 Yes 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6141-6142 Clinically significant macular edema FPP1208 based on hard exudates 8560 00 None 16 01 Questionable 27 02 Yes 1134 88 Blank but applicable 21574 Blank 6143-6144 Central circle clinically significant FPP1209 macular edema based on hard exudates 8580 00 None 23 02 Yes 1134 88 Blank but applicable 21574 Blank 6145-6146 Retinal detachment FPP1210 8599 00 None 1 01 Questionable 3 02 Yes 1134 88 Blank but applicable 21574 Blank 6147-6148 Central circle retinal detachment FPP1211 8603 00 None 1134 88 Blank but applicable 21574 Blank 6149-6150 Photocoagulation treatment in arcades FPP1212 8578 00 None 4 01 Questionable 21 02 Yes 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6151-6152 Photocoagulation treatment outside FPP1214 arcades 8581 00 None 2 01 Questionable 20 02 Yes 1134 88 Blank but applicable 21574 Blank 6153-6154 Other miscellaneous abnormalities FPP1220 8059 00 None 97 01 Questionable 447 02 Yes 1134 88 Blank but applicable 21574 Blank 6155-6156 Other miscellaneous central circle FPP1221 abnormalities 8563 00 None 40 02 Yes 1134 88 Blank but applicable 21574 Blank 6157-6158 Answer drusen questions FPP1228 1620 00 No 6867 02 Yes 116 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6159-6160 Hard drusen See note FPP1230 1824 00 None 849 01 Questionable 5511 02 Yes 419 08 Can't grade 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6161-6162 Soft drusen See note FPP1240 7167 00 None 391 01 Questionable 926 02 Yes 119 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6163-6164 Drusen area: grid See note FPP1250 3391 00 None 2786 01 Less than a circle of 95 microns in diameter (standard circle C0) 1719 02 Less than a circle of 375 microns in diameter (standard circle C2) 351 03 Less than a circle of 960 microns in diameter (standard circle O2) 147 04 Greater than or equal to a circle of 960 microns in diameter (standard circle O2) 209 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6165-6166 Drusen area: outside See note FPP1260 5096 00 None 2131 01 Less than a circle of 95 microns in diameter (standard circle C0) 872 02 Less than a circle of 375 microns in diameter (standard circle C2) 213 03 Less than a circle of 960 microns in diameter (standard circle O2) 132 04 Greater than or equal to a circle of 960 microns in diameter (standard circle O2) 159 08 Can't grade 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ FINDINGS ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6167-6168 Drusen area: central circle See note FPP1262 5513 00 None 1881 01 Less than a circle of 95 microns in diameter (standard circle C0) 561 02 Less than a circle of 375 microns in diameter (standard circle C2) 125 03 Less than a circle of 960 microns in diameter (standard circle O2) 16 04 Greater than or equal to a circle of 960 microns in diameter (standard circle O2) 507 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6169-6170 Drusen area: inner circle See note FPP1264 4063 00 None 2682 01 Less than a circle of 95 microns in diameter (standard circle C0) 1308 02 Less than a circle of 375 microns in diameter (standard circle C2) 251 03 Less than a circle of 960 microns in diameter (standard circle O2) 122 04 Greater than or equal to a circle of 960 microns in diameter (standard circle O2) 177 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6171-6172 Central circle soft drusen See note FPP1266 7772 00 None 71 01 Questionable 297 02 Yes 463 08 Can't grade 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ FUNDUS PHOTOGRAPHY ------------------------------------------------------------------------ SUMMARY SCORES ------------------------------------------------------------------------ Positions Item description SAS name Counts and code Notes ------------------------------------------------------------------------ 6173-6174 Summary diabetic retinopathy score See note FPPSURET 7764 00 None 327 01 Mild 94 02 Moderate 26 03 Proliferative 392 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6175-6176 Summary age-related maculopathy score See note FPPSUMAC 7268 00 None 885 01 Early 55 02 Late 395 08 Can't grade 1134 88 Blank but applicable 21574 Blank 6177-6178 Summary drusen score See note FPPSUDRU 1979 00 None 867 01 Questionable 5640 02 Present 117 08 Can't grade 1134 88 Blank but applicable 21574 Blank NHANES III Examination Data File ------------------------------------------------------------------------ THIS PAGE INTENTIONALLY LEFT BLANK NOTES FPP1020: Fundus When the fundus was absent (FPP1020=00), the grader was instructed to stop. All ensuing fields, FPP1030 through FPP1270, were then left blank by the grader. During data processing, the blank fields were recoded "88 Blank but applicable." FPP1060: Gradability status Not all photographs were gradable. The principal reasons were related to the camera (e.g., malfunction, poor focus, dirty lens) and to the examinee (e.g., cataracts, eye movement, corneal change, poor pupil dilation, lens implants). The grader was instructed to stop when the entire field was ungradable (FPP1060=06), at which point the remaining fields were left blank. During data processing, the blank fields were recoded "88 Blank but applicable." FPP1070: Diabetic retinopathy level This variable represents the current state of severity of retinopathy in the eye. As such, it differs from the summary diabetic retinopathy score (FPPSURET) which represents the combination of current and past retinopathy status. FPP1230-FPP1266: Drusen details Drusen vary in appearance, merging at one end of the spectrum with the normal fundus background and at the other end with diffuse degeneration of the retinal pigment epithelium. Typical small drusen usually appear as individual, round, flat spots in the plane of the retinal pigment epithelium. They may be pale yellowish-white, contrasting sharply with the surrounding retinal pigment epithelium, or only slightly more pale than the retinal pigment epithelium and easily overlooked, even with careful examination of well-focused photographs. Larger drusen typically are yellow-white in color and often have visible thickness. Some have sharp margins and a solid, nodular appearance, whereas others have indistinct margins and a softer, more liquid appearance. Drusen may be distributed as individual spots or may appear to merge with adjacent drusen. In NHANES III, two characteristics of drusen type (hard or soft) and area were graded in a semi-quantitative fashion within and outside the grid. Small punctate drusen (usually less than 95 microns in diameter) were classified as hard drusen; larger drusen were classified as soft. No attempt was made to further characterize soft drusen by appearance as soft distinct or indistinct. Drusen area was estimated within a central circle of the grid, within the grid, and outside the grid. The area covered by drusen was estimated by mentally moving together all hard or soft drusen as if they were confluent and comparing this area with those of standard circles. The estimate of drusen area was classified into one of four categories: smaller than a circle with a diameter of 95 microns (comparable to the 63-micron diameter circle used in a 30-degree field), smaller than a circle with a diameter of 375 microns (250-micron diameter in a 30-degree field), smaller than a circle with a diameter of 960 microns (640-micron diameter in a 30-degree field), or equal to or larger than a circle with a diameter of 960 microns. FPPPHOTO: Photographic status Fundus photographs were not taken on all examinees who came to the mobile examination center. The principal reasons were refusal to cooperate, equipment failure, physical inability, and insufficient time. FPPSUDRU: Summary drusen score The summary drusen score was derived from a combination of values from several variables. Definite drusen present: FPP1230, hard drusen, and/or FPP1240, soft drusen, were coded "02 Yes." Questionable drusen present: Definite drusen were not present, and FPP1230, hard drusen, and/or FPP1240, soft drusen, were/was coded "01 Questionable." No drusen present: Neither definite nor questionable drusen was present, and FPP1230, hard drusen, and/or FPP1240, soft drusen, were/was coded "00 None." Cannot grade drusen: FPP1230, hard drusen, and FPP1240, soft drusen, were both coded "08 Can't grade." Blank but applicable: FPP1060, gradability, was coded "06 Entire field ungradable," or FPP1020, fundus, was coded "00 Absent" or "88 Blank but applicable." FPPSUMAC: Summary age-related maculopathy score The summary age-related maculopathy score was derived from a combination of values from several variables. A detailed description of lesions as defined by the Wisconsin Age-Related Maculopathy Grading System is available (Klein, 1991; NTIS, 1991). Late age-related maculopathy: At least one of the following variables was coded "02 Yes." FPP1174, geographic atrophy FPP1176, sub-retinal hemorrhage FPP1178, sub-retinal fibrous scar FPP1180, sensory serous (sub-retinal) detachment Early age-related maculopathy: At least one of the following three sets of conditions was met. FPP1172, degeneration of retinal pigment epithelium (RPE), was coded "02 Yes," and (FPP1230, hard drusen, and/or FPP1240, soft drusen, were/was coded "02 Yes"). FPP1182, hyperpigmentation, was coded "02 Yes," and (FPP1230, hard drusen, and/or FPP1240, soft drusen, were/was coded "02 Yes"). FPP1240, soft drusen, was coded "02 Yes," and FPP1250, grid area, was coded 02-04 (equal to or greater than a circle 95 microns in diameter). No age-related maculopathy: Early and late age-related maculopathy definitions were not met, and FPP1240, soft drusen, was coded 00-02 (gradable). "Cannot grade" age-related maculopathy: Early and late age-related maculopathy definitions were not met, and FPP1240, soft drusen, was coded "08 Can't grade." Blank but applicable: FPP1060, gradability, was coded "06 Entire field ungradable," or FPP1020, fundus, was coded "00 Absent" or "88 Blank but applicable." FPPSURET: Summary diabetic retinopathy score The summary diabetic retinopathy score was derived from a combination of values from several variables. That is, it combines the diabetic retinopathy level variable (FPP1070) and history of treatment for proliferative diabetic retinopathy (using the photocoagulation treatment outside the arcades variable (FPP1214) as a marker). A detailed description of lesions as defined by The Early Treatment Diabetic Retinopathy Study (ETDRS) is available in the ETDRS report #10 (The Early Treatment Diabetic Retinopathy Study, 1991). The NHANES III fundus photo grading protocol (NTIS, 1995) describes methods of assigning diabetic levels. Proliferative diabetic retinopathy: At least one of the following two sets of conditions was met. FPP1070, diabetic retinopathy level, was coded 060-070. FPP1070, diabetic retinopathy level, has a code of anything other than "012 Non-diabetic retinopathy," and FPP1214, photocoagulation treatment outside arcades, was coded "02 Yes." Moderate/severe non-proliferative retinopathy: FPP1070, diabetic retinopathy level, was coded "041 Moderate non-proliferative" or "051 Severe non-proliferative." Mild non-proliferative retinopathy: FPP1070, diabetic retinopathy level, was coded "020 Microaneurysms only" or "031 Early non-proliferative." No diabetic retinopathy: FPP1070, diabetic retinopathy level, was coded 010-015. "Cannot grade" diabetic retinopathy: FPP1070, diabetic retinopathy level, was coded "088 Can't grade." Blank but applicable: FPP1060, gradability, was coded "06 Entire field ungradable," or FPP1020, fundus, was coded "00 Absent" or "88 Blank but applicable."