Table 2.

Diagnosis code-only algorithms performance

PrimaryPredictedTrueSensPPVSpecKappa
Algorithm: synchronous
LungOverall6,4456,7890.740.780.980.73 (0.72–0.74)
Adenocarcinoma2,6432,8060.750.790.970.74 (0.72–0.75)
Carcinoma5395710.750.790.970.74 (0.70–0.77)
NSCLC6647450.730.820.970.74 (0.71–0.77)
Other7237840.740.800.990.75 (0.73–0.78)
SCLC1,0791,1440.740.780.970.72 (0.69–0.74)
Squamous7977390.720.670.980.68 (0.65–0.71)
BreastOverall2942030.600.411.000.49 (0.43–0.54)
Her2-/Hr+167860.570.291.000.39 (0.31–0.46)
Her2+/ Hr(±)34310.550.501.000.52 (0.37–0.67)
Other55500.600.551.000.57 (0.46–0.68)
Triple (−)38360.690.661.000.67 (0.55–0.80)
SkinOverall1972300.720.841.000.78 (0.73–0.82)
MMJN**0.430.601.000.50 (0.15–0.85)
Nevi and melanomas1772060.720.841.000.77 (0.73–0.82)
Other15170.820.931.000.87 (0.75–1.00)
Algorithm: Lifetime
LungOverall12,1266,7890.850.480.890.55 (0.54–0.56)
Adenocarcinoma4,8072,8060.860.500.880.56 (0.55–0.58)
Carcinoma7805710.830.610.920.65 (0.62–0.68)
NSCLC1,1027450.840.570.890.61 (0.58–0.64)
Other1,3597840.840.490.930.58 (0.55–0.60)
SCLC2,4111,1440.860.410.790.45 (0.42–0.47)
Squamous1,6677390.850.380.930.49 (0.46–0.51)
BreastOverall1,4672030.760.110.980.18 (0.16–0.21)
Her2−/Hr+701860.740.090.980.16 (0.12–0.19)
Her2+/Hr(+/−)255310.810.100.960.17 (0.11–0.22)
Other217500.720.170.990.27 (0.20–0.34)
Triple (−)294360.830.100.950.17 (0.12–0.23)
SkinOverall8922300.870.220.970.35 (0.31–0.38)
MMJN150*0.860.040.980.07 (0.02–0.13)
Nevi and melanomas6892060.870.260.960.39 (0.35–0.43)
Other53*0.880.280.930.40 (0.26–0.55)
  • For Medicare claims data algorithms identifying synchronous and lifetime BMs based only on the presence of a diagnosis code for secondary cancer of the CNS, this table shows classification accuracy compared with a SEER SBM gold standard. The rows under “Algorithm: Synchronous” represent such an algorithm with the additional criteria that codes must have occurred within 60 days of primary cancer diagnosis, whereas “Algorithm: Lifetime” indicates that codes may have occurred at any time in Medicare claims. “Sens” refers to sensitivity; “spec,” specificity; PPV, positive predictive value. An asterisk (“*”) represents values that are suppressed to avoid reporting data from 1 to 11 cases. MMJN, malignant melanoma in junctional nevi.