Reviewer agreement in scoring 419 abstracts for scientific orthopedics meetings

BACKGROUND

The selection of presentations at orthopedic meetings is an important process. If the peer reviewers do not consistently agree on the quality score, the review process is arbitrary and open to bias. The aim of this study was: (1) to describe the inter-reviewer agreement of a previously designed scoring scheme to rate abstracts submitted for presentation at meetings arranged by the Dutch Orthopedic Association; (2) to test whether the quality of reporting of submitted abstracts increased in the years after the introduction of the scoring scheme; and (3) to examine whether a review process with a larger workload had lower interrater agreement.

METHODS

We calculated intraclass correlation coefficients (ICC) to measure the level of agreement among reviewers using the International Society of the Knee (ISK) quality-of-reporting system for abstracts. Acceptance rate and quality of the abstracts are described.

RESULTS

Of 419 abstracts, 229 (55%) were accepted. Inter-reviewer agreement to rate abstracts was substantial (0.68; 95% CI: 0.47-0.83) to almost perfect (0.95; 95% CI: 0.92-0.97) and did not change over the eligible time period. A smaller proportion of abstracts were accepted after 2004. The mean ISK abstract score (with a maximum of 100 points) for accepted abstracts ranged from 60 (95% CI: 58-63) to 64 (95% CI: 62-66). The mean ISK abstract score for rejected abstracts varied from 46 (95% CI: 40-51) to 51 (95% CI: 47-55). Average scores for accepted and rejected abstracts did not change with time. The degree of workload of the reviewers did not influence their level of agreement.

INTERPRETATION

The ISK abstract rating system has an excellent interobserver agreement. Other scientific orthopedic meetings should consider adopting this ISK rating system for further evaluation in a local or international setting.

Reporting of outcomes in orthopaedic randomized trials: does blinding of outcome assessors matter?

BACKGROUND

Randomization, concealment of treatment allocation, and blinding are all known to limit bias in clinical research. Nonsurgical studies that fail to meet these standards have been reported to inflate the differences between treatment and control groups. While surgical trials can rarely blind surgeons or patients, they can often blind outcome assessors. The aim of this systematic review was threefold: (1) to examine the reporting of outcome measures in orthopaedic trials, (2) to determine the feasibility of blinding in published orthopaedic trials, and (3) to examine the association between the magnitude of treatment differences and the blinding of outcome assessors.

METHODS

We identified and reviewed thirty-two randomized, controlled trials published in The Journal of Bone and Joint Surgery (American Volume) in 2003 and 2004 for the appropriate use of outcome measures. These trials represented 3.4% of all 938 studies published during that time-period. All thirty-two trials were reviewed by two authors for (1) the outcome measures used and (2) the blinding of outcomes assessors. We calculated the magnitude of the treatment effect of the use of blinded compared with unblinded outcome assessors.

RESULTS

Ten (31%) of the thirty-two randomized controlled trials used a modified outcome instrument. Of the ten trials, four failed to describe how the outcome instrument was modified. Nine of the ten articles did not describe how the modified instrument was validated and retested. Sixteen of the thirty-two randomized controlled trials did not report blinding of outcome assessors when blinding would have been possible. Among the studies with continuous outcome measure, unblinded outcomes assessment was associated with significantly larger treatment effects than blinded outcomes assessment (standardized mean difference, 0.76 compared with 0.25; p = 0.01). Similarly, in the studies with dichotomous outcomes, unblinded outcomes assessments were associated with significantly greater treatment effects than blinded outcomes assessments (odds ratio, 0.13 compared with 0.42; p < 0.001). The ratio of odds ratios (unblinded to blinded outcomes assessment) was 0.31, suggesting that unblinded outcomes assessment was associated with a potential for exaggeration of the benefit of the effectiveness of a treatment in our cohort of studies.

CONCLUSIONS

In future orthopaedic randomized controlled trials, emphasis should be placed on detailed reporting of outcome measures to facilitate generalization and the outcome assessors should be blinded, when possible, to limit bias.

Laparoscopic surgery for colon cancer: a systematic review

INTRODUCTION

Colorectal cancer is the second leading cause of cancer-related death in western countries. The objective of this systematic review was to show that laparoscopic-assisted colon resection for cancer is not inferior to open colectomy with respect to cancer survival and perioperative outcomes.

METHOD

We performed a comprehensive literature review. Inclusion criteria were adults aged over 16 years with a colon resection for documented colon cancer and randomized controlled trials with laparoscopic- assisted or open resections. We excluded studies that did not document colon cancer recurrence in their article. We assessed data extraction and study quality and performed a quantitative data analysis.

RESULTS

Six published and 4 unpublished studies fulfilled our inclusion criteria, with a total of 1262 patients. All primary and secondary outcomes showed good homogeneity, except for morbidity, which was described heterogeneously between the studies. There was no disadvantage to laparoscopic colon resection in any of these primary and secondary outcomes, compared with the conventional open technique.

CONCLUSION

The results of this study suggest that, although there is no definitive answer, present evidence indicates that laparoscopic colon cancer resection is as safe and efficacious as the conventional open technique.

Perceptions and competence in evidence-based medicine: Are surgeons getting better? A questionnaire survey of members of the Dutch Orthopaedic Association

BACKGROUND

The Journal of Bone and Joint Surgery, American Volume (The Journal) recently initiated a section called "Evidence-Based Orthopaedics." Furthermore, a level-of-evidence rating is now used in The Journal to help readers in clinical decision-making. Little is known about whether this recent emphasis has influenced surgeons' perceptions about and competence in evidence-based medicine. Therefore, we examined perceptions and competence in evidence-based medicine among Dutch orthopaedic surgeons.

METHODS

Members of the Dutch Orthopaedic Association were surveyed to examine their attitudes toward evidence-based medicine and their competence in evidence-based medicine. We evaluated competences using a newly developed instrument tailored to surgical practice.

RESULTS

Of the 611 members, 367 surgeons (60%) responded. Orthopaedic surgeons welcomed evidence-based medicine. Practical evidence-based medicine resources were perceived as the best method to move from opinion-based or experience-based to evidence-based practice. Four variables were significantly and positively associated with the competence instrument: (1) a younger age, particularly between thirty-six and forty-five years (p = 0.007), (2) experience of less than ten years (p = 0.032), (3) having a PhD degree (p < 0.001), and (4) working in an academic or teaching setting (p = 0.004). The majority of the respondents were aware of The Journal's evidence-based medicine section (84%) and level-of-evidence ratings (65%), and 20% used The Journal's evidence-based medicine abstracts in clinical decision-making. This increased awareness of evidence-based medicine was also reflected in the frequent use of Cochrane reviews in clinical decision-making (27% of the respondents). Surgeons who used and those who were aware of but did not use The Journal's evidence-based medicine abstracts or Cochrane reviews in clinical decision-making had significantly higher competence instrument scores than those who were unaware of these resources (p = 0.03 and p < 0.001, respectively).

CONCLUSIONS

Evidence-based medicine is welcomed by Dutch orthopaedic surgeons. The recent emphasis on evidence-based medicine is reflected in an increased awareness about The Journal's evidence-based medicine section, levels of evidence, and the largest evidence-based medicine resource: the Cochrane reviews. Younger orthopaedic surgeons had better knowledge about evidence-based medicine. The development and use of evidence-based resources as well as preappraised summaries such as The Journal's evidence-based medicine abstracts and Cochrane reviews were perceived as the best way to move from opinion-based to evidence-based orthopaedic practice.

Management of spleen injuries in the adult trauma population: a ten-year experience

BACKGROUND

Increasing awareness of the postoperative risks associated with splenectomies has led physicians and surgeons to use an alternative nonoperative strategy in handling traumatic spleen injuries. Our primary objective was to compare clinical outcomes between operative and nonoperative managements in adult patients with blunt splenic injuries. The secondary objective was to assess the changes in the patterns of managing splenic injuries in the past 10 years.

METHODS

We performed a retrospective chart review on 266 adult patients with a spleen injury who were admitted to a tertiary trauma centre in Ontario between 1992 and 2001. We grouped and compared the patients according to the treatment received, either operative or nonoperative. Frequencies and confidence intervals are reported. Categorical variables were compared with chi-square or Fisher's exact tests. Continuous variables were reported as median and quartile (Q) and were compared with the nonparametric Mann-Whitney U test.

RESULTS

Of 266 patients, 118 had surgery and 148 were managed nonoperatively. The mortality rate was similar between operative and nonoperative groups (9.3% v. 6.8%, p = 0.49), respectively. The rate of any complication was 47.9% for the operative group and 37.9% for the nonoperative group. The median length of stay in hospital was significantly higher in the operative group than in the nonoperative group (21.0 [Q 11.0-40.5] v. 14.0 [Q 7.0-31.5] d, p < 0.001), respectively. This difference was more likely related to a higher proportion of patients having injury severity scores greater than 25 in the operative group. The rate of nonoperative management of spleen injuries was significantly increased from 48.5% to 63.1% between 1992-1996 and 1997-2001 (p = 0.02).

CONCLUSION

The present study has shown that nonoperative management of blunt spleen trauma has increased over time and has acceptable mortality and complication rates in selected patients. Additional prospective studies are needed to assess the feasibility and safety of nonoperative management in adult spleen injuries. Furthermore, the management of traumatic spleen injuries with respect to associated injuries, such as head injuries or intra-abdominal injuries, needs ongoing evaluation.

A cost comparison of off-pump CABG versus on-pump CABG at one-year: The Canadian off-pump CABG registry

BACKGROUND

Evidence suggests that off-pump coronary artery bypass graft surgery (CABG) is as safe and effective as on-pump CABG, and the cost of initial hospitalization for off-pump CABG is less expensive than on-pump CABG. However, it is uncertain whether the cost savings are sustained over a longer period of time.

OBJECTIVE

To assess in-hospital and one-year direct medical costs of off-pump CABG versus on-pump CABG in the context of the Canadian health care system.

METHODS AND RESULTS

From March 2001 to December 2002, 1657 consecutive patients enrolled in the Canadian Off-Pump CABG Registry were compared with 1693 consecutive on-pump patients from Hamilton Health Sciences CABG database. At one year, patients of both groups were followed by telephone interview. An economic analysis was conducted from the perspective of the Ontario Ministry of Health and Long-Term Care, and the data analysis was based on propensity score-matched registry patients (1233 pairs) to ensure the comparability of the two study groups. Clinical event and resource use information was collected from all patients. Unit costs from the Hamilton Health Sciences case-costing system were used to estimate hospital costs; all costs were reported in 2003 Canadian dollars. Sensitivity analyses were performed to account for uncertainties. The cost of initial hospitalization for off-pump CABG was significantly less than on-pump CABG (11,744 dollars versus 13,720 dollars, P < 0.001). Although follow-up costs were similar between the groups, the one-year total cost per patient for off-pump CABG remained significantly less than on-pump CABG (12,063 dollars versus 14,141 dollars, P < 0.001).

CONCLUSION

Off-pump CABG offers significant savings during initial hospitalization that are also sustained after one year.

Practice patterns for deep vein thrombosis prophylaxis in minimal-access surgery

BACKGROUND

There are no comprehensive evidence-based guidelines for deep vein thrombosis (DVT) prophylaxis in patients undergoing minimal-access surgery (MAS).

METHODS

We completed a cross-sectional survey of general surgeons practising in Ontario, in order to establish current practice patterns for DVT prophylaxis for MAS procedures.

RESULTS

The mean duration of practice of respondents was 15.4 years, with most (67.0%) practising outside an academic centre. For minor MAS, most surgeons do not give DVT prophylaxis (73.8% in laparoscopic cholecystectomy and 63.7% in laparoscopic inguinal hernia repair). For major MAS, a minority of surgeons do not give DVT prophylaxis (4.1% in laparoscopic colorectal surgery and 13.6% in laparoscopic splenectomy). However, there remains considerable variation in the mechanism (pharmacological, mechanical), approach and duration (perioperative, postoperative) of DVT prophylaxis among respondents in all case scenarios evaluated. Academic surgeons and surgeons in practice for 15 years or less are more aggressive with preoperative heparin administration.

CONCLUSIONS

There is substantial and important variability in the current practice of general surgeons with respect to DVT prophylaxis for MAS. Considerable benefit will be derived from clinical trials that provide data to establish appropriate DVT prophylaxis guidelines for MAS.

Pulse Low Dose Steroids Attenuate Post-Cardiopulmonary Bypass SIRS; SIRS I

BACKGROUND

Cardiopulmonary bypass (CPB) initiates inflammation that contributes to multiorgan dysfunction (SIRS). Steroids have been demonstrated to attenuate this response; however, resistance to use steroids remains because of potential adverse effects of the high doses used. This study examines a lower dose steroid protocol for safety and attenuation of SIRS.

METHODS

Sixty patients undergoing CPB were randomized to pulse low doses of methylprednisolone (250 mg given twice IV) or placebo in this RCT. Outcomes pertaining to hemodynamics, ventilator requirement, arrhythmia, and metabolic derangements were recorded. Post-operative glucose control and gastrointestinal prohylaxis was instituted in all patients.

RESULTS

IL-6 concentrations were lower in the steroid group at 4 and 8 h post-operatively (P < 0.0001). The steroid group demonstrated more normothermia (37.2 degrees C versus 37.6 degrees C, P = 0.002), better hemodynamic stability with less requirement for inotropes or vasopressors (0% versus 27.6%, P = 0.005), higher SVRIs (1840 versus 1340 DSm2/cm5, P = 0.002), and higher mean arterial pressures (79 versus 74 mmHg, P = 0.03). The steroid group had a shorter duration of intubation (7.7 versus 10.7 h, P = 0.02), a shorter length of ICU stay (1.0 versus 2.0 days, P = 0.03), and less blood loss (505 versus 690 ml, P = 0.04) with no difference in post-operative blood glucose levels or complications.

CONCLUSIONS

Patients undergoing cardiopulmonary bypass receiving low pulse dose steroids had better hemodynamics, shorter mechanical ventilation times, less blood loss, and required less time in the ICU compared to those receiving placebo. Therefore, this study demonstrates that prophylactic low dose steroids attenuate the SIRS response to CPB without resulting in any untoward side-effects.

Tranexamic acid for hemostasis in the surgical treatment of metastatic tumors of the spine

STUDY DESIGN

This is a retrospective study of sequential cohorts.

OBJECTIVE

To assess the efficacy of tranexamic acid in decreasing operative blood loss and the need for intraoperative transfusion in metastatic spine surgery.

SUMMARY OF BACKGROUND DATA

Significant published data have established the efficacy of antifibrinolytic drugs in limiting surgical bleeding during heart surgery and total joint replacement. One study in scoliosis suggested benefit in spine surgery as well.

METHODS

During a 6-month trial period, 14 patients with spine cancer undergoing palliative intralesional tumor excision and concomitant instrumentation to stabilize the spine in the hands of a single surgeon were administered tranexamic acid intraoperatively in the attempt to minimize operative blood loss. They were then compared to the immediately preceding 14 patients.

RESULTS

Estimated operative blood loss was 1385 mL in the study group treated with tranexamic acid and 1815 mL in controls not receiving the drug, and was not found to be significantly decreased in this study.

CONCLUSIONS

Control of operative bleeding in metastatic spine surgery can be problematical. Optimum protocol might include routine preoperative angiographic tumor embolization to decrease lesion vascularity in all cases, but angiography is not without risk. Noninvasive prophylaxis of tumor bleeding would have obvious desirable advantages but was, unfortunately, not achieved in this study.

Functional gastrointestinal disorders and mood disorders in patients with inactive inflammatory bowel disease: prevalence and impact on health

BACKGROUND

Symptoms of functional gastrointestinal disorders (FGID) associated with mood disorders (MD), such as depression and anxiety, occur in some patients with quiescent inflammatory bowel disease (IBD) and could be caused by changes in gut motility, visceral hypersensitivity, or psychological dysfunction. We assessed the prevalence of FGID symptoms and mood disorders in ambulatory patients with quiescent IBD and examined their impact on health-related quality of life (HRQOL) and use of health resources.

METHODS

Consecutive ambulatory patients with IBD completed a survey of Rome II criteria for FGID, the Hospital Anxiety and Depression Survey, HRQOL indices, and health resource utilization. Logistic and linear regression analyses tested for predictors of FGID and HRQOL.

RESULTS

Of 361 patients surveyed, 149 (44 ulcerative colitis [UC] and 105 Crohn's disease [CD]) had inactive IBD during the previous 12 months. Symptoms of at least 1 FGID occurred in 81.9%. Functional anorectal disorders were the most prevalent (53.7%) followed by functional bowel disorders (51.7%), and both were of greater prevalence than in the Canadian population (41.6% and 22.6%, respectively). Irritable bowel syndrome symptoms were more common in inactive CD than in UC (26% versus 9.1%, P = .01) and functional constipation was more common in inactive UC than in CD (26.2% versus 5.8%, P < .01). MD occurred in 27.3% of UC and 31.3% of CD patients. Age > or =40 years and anxiety independently predicted an FGID. Both FGID symptoms and MD were associated with impaired HRQOL and increased use of health services.

CONCLUSIONS

Many patients with inactive IBD have symptoms compatible with FGID. Both FGID-like symptoms and MD are associated with impaired HRQOL and increased health resource utilization. Recognition and treatment of FGID and MD could potentially improve daily functioning of IBD patients.

The Canadian off-pump coronary artery bypass graft registry: a one-year prospective comparison with on-pump coronary artery bypass grafting

BACKGROUND

The authors sought to examine in-hospital and one-year outcomes of off-pump coronary artery bypass grafting (CABG) and to determine the subgroups of patients most likely to benefit from the off-pump procedure in a regular surgical practice.

METHODS

From March 2001 to December 2002, 1657 consecutive patients were treated with off-pump CABG and 1693 consecutive patients were treated with on-pump CABG. Propensity score modelling was performed to control for treatment and selection bias. A propensity-matched analysis was performed to identify factors associated with survival benefit from the off-pump procedure.

RESULTS

The mortality was similar postoperatively and at one year after surgery. The rate of stroke was decreased in the off-pump group postoperatively (OR=0.49, 95% CI 0.23 to 1.06) and significantly at one year after surgery (OR=0.49, 95% CI 0.27 to 0.90). A significant reduction in acute renal dialysis and a significant increase in myocardial infarction rates were seen in off-pump patients during the initial hospitalization but these differences disappeared during the follow-up period. The number of grafts completed was significantly lower in off-pump CABG than in on-pump CABG (2.62+/-1.00 versus 3.36+/-0.92, respectively; P<0.001). Hospital length of stay and the percentage of patients who required mechanical ventilation were significantly lower in the off-pump group than in the on-pump group. At one year after surgery, the adjusted rate of coronary angiogram and revascularization was similar between the two groups, and the adjusted rate of self-reported angina and memory status was significantly better in the off-pump CABG group. Almost all subgroups of patients had a neutral effect or a survival benefit with the off-pump technique.

CONCLUSIONS

The results from a Canada-wide multicentre registry showed the safety and effectiveness of off-pump CABG in most subgroups of patients in a regular surgical practice.

Ten-year experience with pediatric laparoscopic appendectomy--are we getting better?

BACKGROUND/PURPOSE

The purpose of this study was to compare our initial (1994-1997) and recent (2001-2003) experiences in laparoscopic appendectomy (LA).

METHODS

A 2-year (2001-2003) retrospective chart review of cases of appendicitis was performed and compared with data obtained from 1994 to 1997 cases. Operating and anesthetic times as well as postoperative outcomes were analyzed. Cases of conversion to open appendectomy were included in the analysis.

RESULTS

Two hundred and thirty-three LA cases from 2001 to 2003 were compared with 119 cases from 1994 to 1997. Operating time decreased significantly from 58 to 47 minutes in acute appendicitis (AA) and from 80 to 58 minutes in perforated appendicitis (PA). Anesthetic time decreased significantly in both AA (82 to 71 minutes) and PA (106 to 84 minutes). There were significant decreases in the conversion rate in PA (23.4% to 3.5%), although no change was seen in AA. In PA, the incidence of postoperative abscess decreased from 36.2% to 16.5%. There was no significant decrease in length of stay, amount of analgesia used, time to resume regular diet, or incidence of wound infections and bowel obstructions.

CONCLUSIONS

Ten years of experience in LA has resulted in decreases in anesthetic and operating times for AA and PA as well as decreases in the incidence of abscesses and conversion rates.

Cerebrospinal fluid drainage to prevent paraplegia during thoracic and thoracoabdominal aortic aneurysm surgery: a systematic review and meta-analysis

OBJECTIVES

We undertook a quantitative systematic review of randomized controlled trials (RCTs) and observational studies to determine the effectiveness of cerebrospinal fluid (CSF) drainage to prevent paraplegia in thoracic aneurysm (TA) and thoracoabdominal aortic aneurysm (TAAA) surgery.

METHODS

We included RCTs and cohort studies that met the following criteria: elective or emergent aneurysm surgery involving the thoracic or thoracoabdominal aorta, documentation of postoperative neurologic deficits, and patient age older than 18 years. We excluded studies that reported results in 10 or fewer patients and duplicate publications. We identified eligible studies by searching computerized databases, our own files, and the reference lists of relevant articles and review articles. Database searching, eligibility decisions, relevance and method quality assessments, and data extraction were performed in duplicate with prespecified criteria.

RESULTS

Of 372 publications identified in our search, 14 met our eligibility criteria. Three RCTs reported 289 patients with type I or type II TAAA. Lower limb neurologic deficits occurred in 12% of patients who underwent CSF drainage and 33% of control subjects (number needed to treat, 9; 95% confidence interval [CI], 5-50). The pooled odds ratio (OR) for development of paraplegia in patients in the CSF drainage group was 0.35 (P =.05; 95% CI, 0.12-0.99). Similar results were found in five cohort studies with a control group (pooled OR, 0.26; P =.0002; 95% CI, 0.13-0.53). When all studies were considered together the pooled OR of TA and TAAA was 0.3 (95% CI, 0.17-0.54). There was no statistical heterogeneity among studies included in the meta-analysis. In six cohort studies without a control group, the incidence of paraplegia in high-risk TA and TAAA was 7.6%.

CONCLUSIONS

Evidence from randomized and nonrandomized trials and from cohort studies support the use of CSF drainage as an adjunct to prevent paraplegia when this adjunct is used in centers with large experience in the management of TAAA.

Self-reported awareness and use of the International Classification of Diseases coding of inflammatory bowel disease services by Ontario physicians

RATIONALE

Population and health services research can be performed by linkage analysis of administrative data. However, the robustness of study results is determined by the accuracy of the diagnostic coding.

OBJECTIVES

To estimate the awareness, use and accuracy of the International Classification of Diseases, Ninth Revision (ICD-9) coding by physicians providing services for patients with Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

All Ontario gastroenterologists and a 10% random sample of internists, pediatricians, pediatric or general surgeons, and family physicians were surveyed by postal questionnaire to estimate the frequency and 95% CI of using codes 555 or 556 when billing for CD- and UC-related services, respectively. c2 tests were used for between-group comparisons.

RESULTS

Of the physicians who were surveyed, 67.7% (416 of 614) responded; 258 of 391 (66%) who were still practising in Ontario saw patients with inflammatory bowel disease (IBD), and 54% had more than 10 IBD patients; 86.5% (95% CI 82.4% to 90.6%) were familiar with ICD-9 codes, and 91.4% (95% CI 88.1% to 95.6%) used the codes 555 (CD) or 556 (UC) for billing. Rates of ICD-9 use did not differ by sex but were used more frequently by those graduating after 1981 (P<0.02). Gastroenterologists used ICD-9 IBD codes 555 or 556 significantly more often than all other physicians (P=0.001). Most (more than 75%) Ontario physicians used ICD-9 IBD codes always or frequently when billing for IBD-related services. Few (10%) used these codes to bill for non-IBD-related problems.

CONCLUSIONS

These data suggest that there is acceptable use and accuracy of ICD-9 diagnostic coding for CD and UC services - comparable with results from studies of other diseases. Administrative data may thus be used to undertake epidemiological studies in IBD in Ontario.

Low mortality in ulcerative colitis and Crohn's disease in three regional centers in England

OBJECTIVES

Recent epidemiological studies suggest that mortality rates for inflammatory bowel disease (IBD) are similar to those of the general population. However, most of this work has been done in referred populations or larger urban centers. We intended to estimate mortality rates for ulcerative colitis (UC) and Crohn's disease (CD) in three British district general hospital practices in Wolverhampton, Salisbury, and Swindon.

METHODS

Consecutive patients with CD or UC were identified from 1978 to 1986 and followed prospectively. Demographic data, date and cause of death or health status at December 31, 1993 were used to estimate standardized mortality ratios (SMRs) and 95% confidence intervals.

RESULTS

Sixty-four deaths occurred in 552 patients (UC 41 of 356; CD 23 of 196). The overall SMRs were 103 [95% confidence interval (CI): 79-140] for UC and 94 (95% CI: 59-140) for CD. The respective SMRs were higher only in the first year after diagnosis at 223 (95% CI: 99-439; p = 0.02) and 229 (74-535; p = 0.056), and even then, most subjects died from non-IBD causes (5 of 13). Nonsurvivors were significantly older than survivors in both UC and CD (p < 0.01). The SMR was also significantly greater during a severe first attack of UC at 310 (95% CI: 84-793; p = 0.04). Patients with perianal or colonic CD had an increased SMR [396 (95% CI: 108-335; p = 0.02) and 164 (95% CI: 82-335; p = 0.02)] respectively, partly related to the older mean age (52 vs 32 yr, p < 0.001).

CONCLUSIONS

Mortality rates are not increased in IBD compared with the general population. However, older patients may be at increased risk of dying from other causes early in the disease clinical course.

A critical review of epidemiological studies in inflammatory bowel disease

This review addresses the difficulty in interpreting the results of epidemiological studies in IBD and in making meaningful comparisons between studies. Both ulcerative colitis and Crohn disease appear to be more common in some industrialized countries such as Scandinavia, United Kingdom, North America and less common in Central and Southern Europe, Asia and Africa. Given data showing an increased incidence of ulcerative colitis in the United Kingdom, it is crucial that more studies be conducted in developing countries. While the incidence of Crohn disease has increased strikingly in many areas, the incidence of ulcerative colitis has remained fairly stable in most. This could be due to the rising number of community-based studies, as well as the improved accuracy in diagnosing Crohn disease. Although, the incidence of IBD among Blacks in Africa is low, infection rates are high, life expectancy is lower than in developed countries. Data from the USA suggest that rates are similar in Afro-American and Caucasian populations. Rates for Jewish populations may be slightly higher than in non-Jewish populations but this also varies geographically. Careful attention to genetic, environmental, and socioeconomic factors must be accounted for in these studies. There is no strong evidence to support that IBD is more common in urban than in rural settings and migration towards more accessible health care has not been adequately addressed. Recent epidemiological studies suggest that mortality rates for IBD are similar to that of the general population for the majority of patients. However, older patients with IBD and newly diagnosed cases with severe diseases are at increased risk of dying. Epidemiological studies remain important in assisting with health policy planning and in hypothesis testing of etiological factors. As better diagnostic techniques become widely available and public health registries are increasingly used, it is possible that geographic differences will diminish. International collaborative studies will be better equipped to answer research questions addressing risk factors and disease natural history. We have summarized in Table V the essential criteria to conduct a sound epidemiological study, which would permit future testing of hypotheses among different populations.

A critical review of epidemiological studies in inflammatory bowel disease

This review addresses the difficulty in interpreting the results of epidemiological studies in IBD and in making meaningful comparisons between studies. Both ulcerative colitis and Crohn disease appear to be more common in some industrialized countries such as Scandinavia, United Kingdom, North America and less common in Central and Southern Europe, Asia and Africa. Given data showing an increased incidence of ulcerative colitis in the United Kingdom, it is crucial that more studies be conducted in developing countries. While the incidence of Crohn disease has increased strikingly in many areas, the incidence of ulcerative colitis has remained fairly stable in most. This could be due to the rising number of community-based studies, as well as the improved accuracy in diagnosing Crohn disease. Although, the incidence of IBD among Blacks in Africa is low, infection rates are high, life expectancy is lower than in developed countries. Data from the USA suggest that rates are similar in Afro-American and Caucasian populations. Rates for Jewish populations may be slightly higher than in non-Jewish populations but this also varies geographically. Careful attention to genetic, environmental, and socioeconomic factors must be accounted for in these studies. There is no strong evidence to support that IBD is more common in urban than in rural settings and migration towards more accessible health care has not been adequately addressed. Recent epidemiological studies suggest that mortality rates for IBD are similar to that of the general population for the majority of patients. However, older patients with IBD and newly diagnosed cases with severe diseases are at increased risk of dying. Epidemiological studies remain important in assisting with health policy planning and in hypothesis testing of etiological factors. As better diagnostic techniques become widely available and public health registries are increasingly used, it is possible that geographic differences will diminish. International collaborative studies will be better equipped to answer research questions addressing risk factors and disease natural history. We have summarized in Table V the essential criteria to conduct a sound epidemiological study, which would permit future testing of hypotheses among different populations.