Hidden complexities in assessment of glycemic outcomes: are quality rankings aligned with treatment?
OBJECTIVE
To evaluate facility rankings in achieving <7% A1C levels based on the complexity of glycemic treatment regimens using threshold and continuous measures.


METHODS
We conducted a retrospective administrative data analysis of Veterans Health Administration Medical Centers in 2003-2004. Eligible patients were identified using National Committee for Quality Assurance (NCQA) measure specifications. A complex glycemic regimen (CGR) was defined as receipt of insulin or three oral agents. Facilities were ranked using five ordinal categories based up both z score distribution and statistical significance (P < 0.05). Rankings using the NCQA definition were compared with a subset receiving CGRs using both a <7% threshold and a continuous measure awarding proportional credit for values between 7.9 and <7.0%. Ranking correlation was assessed using the Spearman correlation coefficient.


RESULTS
A total of 203,302 patients (mean age 55.2 years) were identified from 127 facilities (range 480-5,411, mean 1,601); 26.7% (17.9-35.2%) were receiving CGRs, including 22.0% receiving insulin. Mean A1C and percent achieving A1C <7% were 7.48 and 48% overall and 8.32 and 24.8% for those receiving CGRs using the threshold measure; proportion achieved was 60.1 and 37.2%, respectively, using the continuous measure. Rank correlation between the overall and CGR subset was 0.61; 8 of 24 of the highest or lowest ranked facilities changed to nonsignificance status; an additional five sites changed rankings.


CONCLUSIONS
Facility rankings in achieving the NCQA <7% measure as specified differ markedly from rankings using the CGR subset. Measurement for public reporting or payment should stratify rankings by CGR. A continuous measure may better align incentives with treatment intensity.
Pogach
Leonard M
LM
Department of Veterans Affairs New Jersey Healthcare System, East Orange, New Jersey, USA. leonard.pogach@va.gov
Rajan
Mangala
M
Maney
Miriam
M
Tseng
Chin-Lin
CL
Aron
David C
DC
D003695:Delivery of Health Care / Q000592:standards*; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy; D004334:Drug Administration Schedule; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D058014:Veterans Health / Q000706:statistics & numerical data
D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin