Table 4 : Pure red cell aplasia (PRCA) incidence rates.

	Overall
Total number of possible PRCA cases identified from claims data	25
Number of possible PRCA cases identified from claims data with received medical records that underwent medical record review.	17
Number of true positive PRCA cases*	0
Number of possible PRCA cases† identified from claims data for which no medical record was received or received medical records did not contain the required key elements for adjudication	8
At-risk person-time, person-years, total	75,132
PRCA IR‡, true positive events per 1,000 person-years (95% CI)	0.00 (0.00-0.05)

CI: Confidence interval; IR: Incidence rate; PRCA: Pure red cell aplasia
^*Evidence of true positive PRCA identified from claims data using the preliminary
claims-based algorithm and confirmed from medical record review.
^†Evidence of possible PRCA identified from claims data using the preliminary claims-based
algorithm and confirmed from medical record review. Eight claims-identified PRCA cases,
for which no medical record was received, were assumed to be possible positive PRCA cases.
^‡Incidence rate (IR) is defined as the number of new true positive PRCA cases divided by
the total at-risk person-time.