Table 1.
Multimorbidity-Weighted Index Conditions and the Accuracy, Source, and Type of Validation for Respective ICD-9 Codes for the 10 Most Prevalent Conditions in Medicare claims; 2014
| Organ system | Diagnosis | ICD-9 codes found in literature search | Source of Validationa | Record Type | Sample Size in Study | Algorithm | Accuracy (Sensitivity, Specificity, PPV, NPV, Kappab) |
|---|---|---|---|---|---|---|---|
| Cardiovascular | Hypertension | 401.x-405.xx | Chart review | Disease registry | 184 | 2 claims |
SENS: 65% SPEC: 90% PPV: 95% NPV: 50% Kappa: 0.45 [15] |
| 401.x-405.xx, 437.2; exclusion: 250.xx, 430–436, 437.1, 437.9, 438.xx | Chart review | Inpatient, outpatient | 76 | Any claim up to 9 claims | PPV: 93% [16] | ||
| Endocrine | Elevated cholesterol/Hyperlipidemia | 272.0–272.4 | Chart review | Outpatient | 1176 | ≥1 outpatient |
SENS: 85% SPEC: 85% Kappa: 0.70 [17] |
| 272.0–272.4 | Chart review | Disease registry | 184 | 2 claims |
SENS: 95% SPEC: 90% PPV: 90% NPV: 95% Kappa: 0.85 [15] |
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| Ophthalmologic | Cataract | 366–366.4 | Construct validity [18] | N/A | |||
| 13.11, 13.19, 13.20, 13.30, 13.41, 13.42, 13.43, 13.59, 13.69, 13.71 | Construct validity [19] | N/A | |||||
| Endocrine | Diabetes | 250.xx | Chart review | Outpatient | 1176 | ≥1 outpatient claim |
SENS: 97% SPEC: 96% Kappa: 0.92 [17] |
| 250.xx | Chart review | Disease registry | 184 | 2 claims |
SENS: 91% SPEC: 100% PPV: 100% NPV: 90% Kappa: 0.90 [15] |
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| 250.00–250.93 | Chart review | Any encounter | 465 | (1) One claim; (2) Two claims |
SENS: (1) 92%; (2) 64% SPEC: (1) 99%; (2) 99% PPV: (1) 94%; (2) 95% [20] |
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| Musculoskeletal | Osteoarthrosis | 715.xx | Construct validity [21] | N/A | |||
| Endocrine | Hypothyroidism | 244.0, 244.1, 244.9 | Construct validity [22] | N/A | |||
| Renal | Chronic kidney disease, polycystic kidney disease | 403.xx, 405.× 1, 582.xx, 583.xx, 585.x, 586, 593.9 | Chart review | Outpatient | 1176 | ≥1 outpatient claim |
SENS: 62% SPEC: 98% Kappa: 0.62 [17] |
| 585.x, 586 (chronic renal failure) | Chart review | Inpatient | 7050 | (1) Any claim; (2) Primary claim |
SENS: (1) 83%; (2) 85% PPV: (1) 70%; (2) 61% [23] |
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|
585.x, 403.xx, 404.xx, 583.81, 581.81, 250.40, 250.42, 250.80, 250.82 |
Chart review | Inpatient, outpatient | 1186 | Any claim |
PPV: 63% NPV: 54% [24] |
||
| 753.12, 753.13, 753.14 (Polycystic kidney disease) | Chart review | Disease registry | 184 | 2 claims |
SENS: 100% SPEC: 90% PPV: 90% NPV: 100% Kappa: 0.90 [15] |
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| (1) 250.40, 250.41, 250.42, 250.43 (diabetic nephropathy); (2) 403.xx, 404.xx (hypertensive nephropathy); (3) 572.4, 580.xx, 584.xx, 580.0, 580.4, 580.89, 580.9, 582.4, 791.2, 791.3 (acute renal failure); (4) 582.xx, 583.xx, 585.x, 586, 587 (chronic renal insufficiency) | Chart review | Medicare claims | 1852 | Any claim |
SEN: (1) 3%; (2) 7%; (3) 5%; (4) 12% SPEC: (1) 99%; (2) 99; (3) 100%; (4) 99% PPV: (1) 86%; (2) 95%; (3) 97%; (4) 97% NPV: (1) 32%; (2) 33%; (3) 33%; (4) 35% [25] |
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| Pulmonary | Chronic obstructive pulmonary disease (COPD) | 491.xx-494.x, 496 | Chart review | Inpatient | 7050 | (1) Any claim; (2) Primary claim |
SENS: (1) 85%; (2) 79% PPV: (1) 87%; (2) 68% [23] |
| 491.xx, 492.x, 496 | Chart review | Inpatient, outpatient | 12,127 | (1) ≥2 outpatient or ≥ 1 inpatient; (2) ≥3 outpatient or ≥ 2 inpatient | PPV: (1) 64%; (2) 72% [26] | ||
| 491.xx, 492.x, 496 | Chart review | Inpatient | 1221 | Primary claim of 491, 492, or 496 | PPV: 50% [17] | ||
| 490–492.x, 493.22, 496, 518.81, 518.82, 518.84, 799.1 | Chart review | Inpatient | (1) 50; (2) 46; (3) 29; (4) 20 | (1) Age ≥ 25, Primary claim of 490, 491.x, 492.x, 493.22, 496OR Primary claim of 518.81, 518.82, 518.84, 799.1 AND secondary claim of 490, 491.x, 492.x, 493.22, 496; (2) Age ≥ 40, Primary claim of 491.x (except for 491.20), 492.x, 493.22, 496 OR primary claim of 518.81, 518.82, 518.84 AND secondary claim of 491.x (except for 491.20), 492.x, 493.22, 496; (3) Age ≥ 40, primary claim of 491.x, 492.x, 496; (4) Age ≥ 40, primary claim of 491.21 |
SENS: (1) 25%; (2) 24%; (3) 15%; (4) 12% SPEC: (1) 100%; (2) 100%; (3) 100%; (4) 100% PPV: (1) 81%; (2) 85%; (3) 86%; (4) 97% NPV: (1) 94%; (2) 94%; (3) 93%; (4) 93% [27] |
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| 490, 491.xx (all except 491.8), 492.x, 493.xx, 496 | Chart review | Outpatient | 1176 | ≥1 outpatient claim |
SENS: 81% SPEC: 92% Kappa: 0.68 [28] |
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| Cardiovascular | Congestive heart failure | (1) 398.91, 402.×1, 404.× 1, 404.× 3, or 428.xx; (2) 428.xx | Chart review | Inpatient | 908 |
(1) Any claim; (2) Primary claim |
SENS: (1A) 94%; (1B) 55%; (2A) 91%; (2B) 48% PPV: (1A) 43%; (1B) 86%; (2A) 43%; (2B) 86% [29] |
|
398.91, 402.01, 402.11, 402.91, 404.01, 404.03, 404.11, 404.13, 404.91, 404.93, 425.x, 428.xx |
Chart review | Inpatient | 497 | Primary claim |
SENS: 20% SPEC: 100% PPV: 79% NPV: 94% [30] |
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| 398.91, 402.01, 402.11, 402.91, 404.01, 404.03, 404.11, 404.13, 404.91, 404.93, 425.4–425.9, 428.xx | Chart review | Inpatient, outpatient | 172 |
(1) Any claim in 12-month window; (2) Any claim in 24-month window |
SENS: (1) 90%; (2) 90% SPEC: (1) 95%; (2) 94% PPV: (1) 72%; (2) 69% NPV: (1) 99%; (2) 98% [31] |
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|
(1) 428.xx; (2) 402.xx or 428.xx; (3) 398.97, 402.×1, 404.xx, 415.0, 416.9, 425.4, 428.xx, 429.4, 514, 518.4, 786.0x |
Chart review | Inpatient | 5083 | Any claim |
SENS: (1) 63%; (2) 66%; (3) 67% SPEC: (1) 95%; (2) 93%; (3) 93% PPV: (1) 84%; (2) 79%; (3) 77% NPV: (1) 87%; (2) 88%; (3) 88% [32] |
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| 398.91, 402.×1, 402.×3, 404.× 1, 404.×3, 422.90, 425.4, 425.9, 428.xx | Chart review | Inpatient, outpatient | 400 | ≥1 Primary Discharge or ≥ 3 Secondary Discharge or ≥ 2 Outpatient or ≥ 3 ED or ≥ 2 Secondary Discharge + ≥1 Outpatient Claim |
SENS: 62% SPEC: 99% PPV: 69% NPV: 98% [33] |
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| 398.91, 402.01, 402.11, 402.91, 404.01, 404.03, 404.11, 404.13, 404.91, 404.93, 414.8, 428.xx | Chart review | Outpatient | 1176 | ≥1 outpatient |
SENS: 77% SPEC: 99% Kappa: 0.74 [17] |
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| 428.xx | Chart review | Disease registry | 184 | 2 claims |
SENS: 87% SPEC: 100% PPV: 100% NPV: 85% Kappa: 0.85 [15] |
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| 402.01, 402.11, 402.91, 428.0–428.9x | Chart review | Inpatient | 7050 |
(1) Any claim; (2) Primary claim |
SENS: (1) 89%; (2) 85% PPV: (1) 71%; (2) 87% [23] |
||
| (1) 428.xx; (2) 428.xx with other codes; (3) 402.01, 402.11, 425.x, 429.3, and 514 | Systematic review | Inpatient, outpatient | 35 | Various algorithms due to systematic review | PPV: (1) 84–100%; (2) 77–79%; (3) 14–30% [34] | ||
| Cardiovascular | Atrial fibrillation | 427.31 (atrial fibrillation) or 427.32 (atrial flutter) | Chart review | Inpatient, outpatient, emergency department | 300 | 1 inpatient or 2 outpatient or emergency department | PPV: 96% [35] |
| 427.3x | Chart review | Outpatient | 1176 | ≥1 outpatient |
SENS: 80% SPEC: 99% Kappa: 0.81 [17] |
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| 427.31, 427.32 | Systematic review | Inpatient, outpatient | 16 | Various algorithms due to systematic review |
SENS: 57–95% PPV: 70–96% [34] |
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aIf the source of validation was a systematic review; the sample size refers to the number of studies included
bThe number within the bracket following the accuracy values indicates the citation number for the reference