J Diabetes Sci Technol. 2008 Jan;2(1):24-32. doi: 10.1177/193229680800200105.
Longitudinal approaches to evaluate health care quality and outcomes: the Veterans Health Administration diabetes epidemiology cohorts.
Journal of diabetes science and technology
Donald R Miller, Leonard Pogach
Affiliations
Affiliations
- Center for Health Quality, Outcomes and Economic Research, Bedford VA Medical Center, Bedford, Massachusetts, USA.
PMID: 19885174
PMCID: PMC2769712 DOI: 10.1177/193229680800200105
Abstract
OBJECTIVE: The Institute of Medicine proposed recently that, while current pay for performance measures should target multiple dimensions of care, including measures of technical quality, they should transition toward longitudinal and health-outcome measures across systems of care. This article describes the development of the Diabetes Epidemiology Cohorts (DEpiC), which facilitates evaluation of intermediate "quality of care" outcomes and surveillance of adverse outcomes for veterans with diabetes served by the Veterans Health Administration (VHA) over multiple years.
METHODS: The Diabetes Epidemiology Cohorts is a longitudinal research database containing records for all diabetes patients in the VHA since 1998. It is constructed using data from a variety of national computerized data files in the VHA (including medical encounters, prescriptions, laboratory tests, and mortality files), Medicare claims data for VHA patients, and large patient surveys conducted by the VHA. Rigorous methodology is applied in linking and processing data into longitudinal patient records to assure data quality.
RESULTS: Validity is demonstrated in the construction of the DEpiC. Adjusted comparisons of disease prevalence with general population estimates are made. Further analyses of intermediate outcomes of care demonstrate the utility of the database. In the first example, using growth curve models, we demonstrated that hemoglobin A1c trends exhibit marked seasonality and that serial cross-sectional outcomes overestimate the improvement in population A1c levels compared to longitudinal cohort evaluation. In the second example, the use of individual level data enabled the mapping of regional performance in amputation prevention into four quadrants using calculated observed to expected major and minor amputation rates. Simultaneous evaluation of outliers in all categories of amputation may improve the oversight of foot care surveillance programs.
CONCLUSIONS: The use of linked, patient level longitudinal data resolves confounding case mix issues inherent in the use of serial cross-sectional data. Policy makers should be aware of the limitations of cross-sectional data and should make use of longitudinal patient databases to evaluate clinical outcomes.
Keywords: A1c; amputations; databases; diabetes; registry
References
- Jt Comm J Qual Improv. 2002 Oct;28(10):555-65 - PubMed
- Health Aff (Millwood). 2007 Mar-Apr;26(2):w156-68 - PubMed
- Womens Health Issues. 2006 Nov-Dec;16(6):361-71 - PubMed
- Lancet. 1998 Sep 12;352(9131):837-53 - PubMed
- Med Care. 2005 Jan;43(1):4-11 - PubMed
- Diabetes Care. 2003 Nov;26(11):3042-7 - PubMed
- Health Serv Res. 2006 Apr;41(2):564-80 - PubMed
- J Gen Intern Med. 2006 Mar;21 Suppl 3:S47-53 - PubMed
- Diabetes Care. 2004 May;27 Suppl 2:B90-4 - PubMed
- Am J Hypertens. 2006 Feb;19(2):161-9 - PubMed
- Lancet. 2000 Jan 22;355(9200):253-9 - PubMed
- Diabetes Care. 2007 Feb;30(2):245-51 - PubMed
- Arch Intern Med. 2005 Dec 12-26;165(22):2631-8 - PubMed
- N Engl J Med. 1993 Sep 30;329(14):977-86 - PubMed
- Diabetes Care. 2004 May;27 Suppl 2:B10-21 - PubMed
- Med Care. 2006 Aug;44(8):779-87 - PubMed
- Diabetes Care. 2007 Jul;30(7):1689-93 - PubMed
- Int J Qual Health Care. 2006 Sep;18 Suppl 1:26-30 - PubMed
- Med Care. 2007 Apr;45(4):308-14 - PubMed
- Med Care. 2005 Jan;43(1):88-92 - PubMed
- Med Care. 2000 Jun;38(6 Suppl 1):I38-48 - PubMed
- Diabetes Care. 2005 Aug;28(8):1890-7 - PubMed
- Arch Intern Med. 2003 Apr 28;163(8):922-8 - PubMed
- Am J Epidemiol. 2005 Mar 15;161(6):565-74 - PubMed
- Diabetes Care. 2003 Mar;26(3):917-32 - PubMed
- N Engl J Med. 2006 Nov 2;355(18):1845-7 - PubMed
- Ann Intern Med. 2006 Apr 4;144(7):465-74 - PubMed
- Popul Health Metr. 2006 Jul 06;4:7 - PubMed
- Am J Manag Care. 2005 Dec;11(12):797-804 - PubMed
- Med Care Res Rev. 2003 Jun;60(2):253-67 - PubMed
- Lancet. 2003 Jun 14;361(9374):2005-16 - PubMed
- Med Care. 2006 May;44(5):439-45 - PubMed
- Diabetes Care. 2005 Apr;28(4):950-5 - PubMed
- MMWR Morb Mortal Wkly Rep. 2003 Sep 5;52(35):833-7 - PubMed
- Am J Manag Care. 2007 Feb;13(2):73-9 - PubMed
- JAMA. 2007 Feb 7;297(5):520-3 - PubMed
- Am J Manag Care. 2004 Feb;10(2 Pt 2):171-80 - PubMed
- Int J Qual Health Care. 2007 Dec;19(6):368-76 - PubMed
- Am J Manag Care. 2004 Nov;10(11 Pt 2):886-92 - PubMed
- Diabetes Care. 2003 Nov;26(11):3017-23 - PubMed
- Diabetologia. 2004 Dec;47(12):2051-8 - PubMed
- Popul Health Metr. 2006 Apr 10;4:2 - PubMed
- Am J Manag Care. 2007 Mar;13(3):133-40 - PubMed
- Health Serv Res. 2005 Dec;40(6 Pt 1):1818-35 - PubMed
- Jt Comm J Qual Patient Saf. 2006 Apr;32(4):206-13 - PubMed
Publication Types