Gerry A Parsons

The University of Calgary, Calgary, Alberta, Canada

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Publications (7)23.74 Total impact

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    ABSTRACT: The goal of this study was to assess the validity of the International Classification of Disease, 10th Version (ICD-10) administrative hospital discharge data and to determine whether there were improvements in the validity of coding for clinical conditions compared with ICD-9 Clinical Modification (ICD-9-CM) data. We reviewed 4,008 randomly selected charts for patients admitted from January 1 to June 30, 2003 at four teaching hospitals in Alberta, Canada to determine the presence or absence of 32 clinical conditions and to assess the agreement between ICD-10 data and chart data. We then re-coded the same charts using ICD-9-CM and determined the agreement between the ICD-9-CM data and chart data for recording those same conditions. The accuracy of ICD-10 data relative to chart data was compared with the accuracy of ICD-9-CM data relative to chart data. Sensitivity values ranged from 9.3 to 83.1 percent for ICD-9-CM and from 12.7 to 80.8 percent for ICD-10 data. Positive predictive values ranged from 23.1 to 100 percent for ICD-9-CM and from 32.0 to 100 percent for ICD-10 data. Specificity and negative predictive values were consistently high for both ICD-9-CM and ICD-10 databases. Of the 32 conditions assessed, ICD-10 data had significantly higher sensitivity for one condition and lower sensitivity for seven conditions relative to ICD-9-CM data. The two databases had similar sensitivity values for the remaining 24 conditions. The validity of ICD-9-CM and ICD-10 administrative data in recording clinical conditions was generally similar though validity differed between coding versions for some conditions. The implementation of ICD-10 coding has not significantly improved the quality of administrative data relative to ICD-9-CM. Future assessments like this one are needed because the validity of ICD-10 data may get better as coders gain experience with the new coding system.
    Preview · Article · Sep 2008 · Health Services Research
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    ABSTRACT: Hospital discharge data are used extensively in health research. Given the clinical differences between ST segment elevation myocardial infarction (STEMI) and non-ST segment elevation myocardial infarction (NSTEMI), it is important that these entities be distinguishable in a medical record. The authors sought to determine the extent to which the type of MI is recorded in medical records, as well as the consistency of this designation within individual records. Records of all MI patients admitted to a tertiary care centre in Canada from April 1, 2000, to March 31, 2001, were reviewed. Documentation and consistency of the use of the terms STEMI (Q wave, ST elevation or transmural MI) or NSTEMI (non-Q wave, subendocardial or nontransmural MI) were assessed in the admission history, progress notes, coronary care unit summary and discharge summary sections of each record. Missing data were common; each chart section mentioned MI type in fewer than one-half of charts. When information was combined, it was possible to determine the type of MI in 81.1% of cases. MI type was consistently described as STEMI in 48.7% of cases, and as NSTEMI in 32.4%. Of concern, MI type was discrepant across sections in 10.5% of cases and missing entirely in 8.4% of cases. The designation of MI cases as STEMI or NSTEMI is both incomplete and inconsistent in hospital records. This has implications for health services research conducted retrospectively using medical record data, because it is difficult to comprehensively study processes and outcomes of MI care if the type cannot be retrospectively determined.
    Full-text · Article · Mar 2008 · The Canadian journal of cardiology
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    ABSTRACT: Psychosocial factors, including social support, affect outcomes of cardiovascular disease, but can be difficult to measure. Whether these factors have different effects on mortality post-acute myocardial infarction (AMI) in men and women is not clear. To examine the association between living alone, a proxy for social support, and mortality postdischarge AMI and to explore whether this association is modified by patient sex. Historical cohort study. All patients discharged with a primary diagnosis of AMI in a major urban center during the 1998-1999 fiscal year. Patients' sociodemographic and clinical characteristics were obtained by standardized chart review and linked to vital statistics data through December 2001. Of 880 patients, 164 (18.6%) were living alone at admission and they were significantly more likely to be older and female than those living with others. Living alone was independently associated with mortality [adjusted hazard ratio (HR) 1.6, 95% confidence interval (CI) 1.0-2.5], but interacted with patient sex. Men living alone had the highest mortality risk (adjusted HR 2.0, 95% CI 1.1-3.7), followed by women living alone (adjusted HR 1.2, 95% CI 0.7-2.2), men living with others (reference, HR 1.0), and women living with others (adjusted HR 0.9, 95% CI 0.5-1.5). Living alone, an easily measured psychosocial factor, is associated with significantly increased longer-term mortality for men following AMI. Further prospective studies are needed to confirm the usefulness of living alone as a prognostic factor and to identify the potentially modifiable mechanisms underlying this increased risk.
    Full-text · Article · Jun 2007 · Journal of General Internal Medicine
  • Hude Quan · Gerry A Parsons · William A Ghali
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    ABSTRACT: Administrative hospital discharge data are widely used to assess quality of care in patients undergoing certain procedures. However, little is known about the validity of administrative coding of procedure data. We conducted a detailed chart review to evaluate the accuracy and completeness of information on procedures in administrative data. We randomly selected 1200 hospital separations in the period April 1, 1996, to March 31, 1997, from administrative discharge data of 3 acute adult hospitals in Calgary, Alberta, Canada. Each separation record in administrative data contains up to 10 procedure coding fields. The corresponding medical charts were reviewed for recording presence or absence of procedures. We then determined sensitivity to quantify the accuracy of coding presence of procedures in administrative data when these are present in the chart data (criterion standard). The agreement between the 2 databases varied greatly across 35 procedures studied. The sensitivity ranged from 0% to 94%. Of 6 major procedures studied, validity of coding was generally good, with 5 procedures having coding sensitivity of 69% and over and only 1 (lysis of peritoneal adhesion) with a low sensitivity of 41%. In contrast, many minor procedures had low sensitivities. Of 29 minor procedures studied, sensitivity was lower than 50% for 15 procedures, between 50% and 79% for 10, and 80% and over for 4. Validity of information on procedures in administrative discharge data appears to be related to type of procedures. Major procedures that are usually performed in operating rooms are reasonably well-coded. Meanwhile, minor procedures that are routinely performed on wards or in radiology departments are generally undercoded.
    No preview · Article · Sep 2004 · Medical Care
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    ABSTRACT: Previous studies have indicated that sex differences may exist in the pharmacological management of acute myocardial infarction (AMI), with female patients being treated less aggressively. To determine if previously reported sex differences in AMI medication use were also evident among all AMI patients treated at hospitals in an urban Canadian city. All patients who had a primary discharge diagnosis of AMI from all three adult care hospitals in Calgary, Alberta, in the 1998/1999 fiscal year were identified from hospital administrative records (n=914). A standardized, detailed chart review was conducted. Information collected from the medical charts included sociodemographic and clinical characteristics, comorbid conditions, and cardiovascular medication use during hospitalization and at discharge. Similar proportions of female and male patients were treated with thrombolytics, beta-blockers, angiotensin-converting enzyme inhibitors, nitrate, heparin, diuretics and digoxin. Among patients aged 75 years and over, a smaller proportion of female patients received acetylsalicylic acid in hospital than did male patients (87% versus 95%; P=0.026). Multivariable logistic regression analysis revealed that, after correction for age, use of other anticoagulants/antiplatelets and death within 24 h of admission, sex was no longer an independent predictor for receipt of acetylsalicylic acid in hospital. Medications prescribed at discharge were similar between male and female patients. The results from this Canadian chart review study, derived from detailed clinical data, indicate that the pattern of pharmacological treatment of female and male AMI patients during hospitalization and at discharge was very similar. No sex differences were evident in the treatment of AMI among patients treated in an urban Canadian centre.
    No preview · Article · Aug 2004 · The Canadian journal of cardiology
  • Hude Quan · Gerry A Parsons · William A Ghali
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    ABSTRACT: Canadian administrative hospital discharge data contain a diagnosis-type indicator for each coded diagnosis that allows researchers to distinguish complications from pre-existing diagnoses. Given that the validity of diagnosis-type indicators is unknown, we conducted a detailed chart review to evaluate the accuracy of diagnosis-type indicators for flagging complications. We obtained administrative hospital discharge data for 1,200 randomly selected adult inpatient separations in Calgary, Alberta, occurring between April 1, 1996 and March 31, 1997. Each discharge record contains up to 16 diagnoses and 16 corresponding diagnosis-type indicators (value of "2"=complication). The corresponding medical charts were reviewed for evidence of diagnoses and complications. A complication was defined as a new diagnosis arising after the start of hospitalization. We determined the extent to which the diagnosis-type indicator in the administrative data agreed with the chart reviewer's assessment (criterion standard) of whether a diagnosis was a complication or not. The agreement for complications between the two databases varied greatly across 12 conditions studied (kappa range: 0-0.72) and was often low (kappa <0.20 for six conditions). Sensitivity ranged from 0 to 57.1% (higher than 50% for only two conditions), indicating a tendency for complications to often be miscoded as baseline comorbidities. In contrast, specificity was generally high (range: 99.0-100%), suggesting that pre-existing conditions were usually appropriately coded as such in the administrative data. The validity of diagnosis-type indicators in Canadian administrative discharge data appears to be poor for some types of complications. This is likely to be of greatest concern in studies that rely solely on diagnosis-type indicators to define complications as outcomes.
    No preview · Article · May 2004 · Journal of Clinical Epidemiology
  • Hude Quan · Gerry A Parsons · William A Ghali
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    ABSTRACT: The comorbidity variables that constitute the Charlson index are widely used in health care research using administrative data. However, little is known about the validity of administrative data in these comorbidities. The agreement between administrative hospital discharge data and chart data for the recording of information on comorbidity was evaluated. The predictive ability of comorbidity information in the two data sets for predicting in-hospital mortality was also compared. One thousand two hundred administrative hospital discharge records were randomly selected in the region of Calgary, Alberta, Canada in 1996 and used a published coding algorithm to define the 17 comorbidities that constitute the Charlson index. Corresponding patient charts for the selected records were reviewed as the "criterion standard" against which validity of the administrative data were judged. Compared with the chart data, administrative data had a lower prevalence in 10 comorbidities, a higher prevalence in 3 and a similar prevalence in 4. The kappa values ranged from a high of 0.87 to a low of 0.34; agreement was therefore near perfect for one variable, substantial for six, moderate for nine, and only fair for one variable. For the Charlson index score ranging from 0 to 5 to 6 or higher, agreement was moderate to substantial (kappa = 0.56, weighted kappa = 0.71). When 16 Charlson comorbidities from administrative data were used to predict in-hospital mortality, 10 comorbidities and the index scores defined using administrative data yielded odds ratios that were similar to those derived from chart data. The remaining six comorbidities yielded odds ratios that were quite different from those derived from chart data. Administrative data generally agree with patient chart data for recording of comorbidities although comorbidities tend to be under-reported in administrative data. The ability to predict in-hospital mortality is less reliable for some of the individual comorbidities than it is for the summarized Charlson index scores in administrative data.
    No preview · Article · Sep 2002 · Medical Care

Publication Stats

856 Citations
23.74 Total Impact Points


  • 2002-2008
    • The University of Calgary
      • Department of Community Health Sciences
      Calgary, Alberta, Canada
  • 2007
    • Institute of Health Economics
      Edmonton, Alberta, Canada