Ontario health technology assessment series
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Ont Health Technol Assess Ser · Jan 2009
Fecal occult blood test for colorectal cancer screening: an evidence-based analysis.
The colorectal cancer (CRC) screening project was undertaken by the Medical Advisory Secretariat (MAS) in collaboration with the Cancer Care Ontario (CCO).In November 2007, the Ontario Health Technology Advisory Committee (OHTAC) MAS to conduct an evidence-based analysis of the available data with respect to colorectal cancer diagnosis and prevention. The general purpose of the project was to investigate the effectiveness, cost effectiveness, and safety of the various methods and techniques used for colorectal cancer screening in average risk people, 50 years of age and older.The options currently offered for colorectal cancer screening were reviewed and five technologies were selected for review:Computed tomographic (CT) colonographyMagnetic resonance (MR) colonographyWireless capsule endoscopy (PillCam Colon)Fecal occult blood test (FOBT)Flexible sigmoidoscopyIn this review, colonoscopy was considered as the "gold standard" technique by which the effectiveness of all other modalities could be evaluated. An economic analysis was also conducted to determine cost-effectiveness of different screening modalities.Evidence-based analyses have been prepared for each of these technologies, as well as summary document that includes an economic analysis, all of which are presented at the MAS Web site: http://www.health.gov.on.ca/english/providers/program/mas/tech/techmn.html ⋯ SINGLE-TEST STUDIES: There is limited direct/indirect evidence that iFOBT has sensitivity/specificity superior to that of unrehydrated gFOBT for CRC detection: sensitivity for gFOBT:13% and 25%pooled iFOBT sensitivity:81%There is evidence that iFOBT and gFOBT have lower sensitivities for adenoma detection than for CRC detection: sensitivity for rehydrated gFOBT22%pooled iFOBT sensitivity28% REPEATED-TEST STUDIES: No trials have examined CRC mortality outcomes after repeated testing of iFOBT. Two RCTs from the United Kingdom and Denmark showed significant reduction in CRC mortality using unrehydrated gFOBT biennially Relative risk reductions of 13% (UK trial) and 16% (Danish trial); absolute difference of 0.1% (UK trial) and 0.2% (Danish trial).No significant reduction in overall mortalityInterval cancers (CRC that develop in the intervals between routine screening) UNITED KINGDOM TRIAL: 236 CRCs detected by positive test, 236 interval CRCs after negative testDANISH TRIAL: 120 CRCs detected by positive test, 146 interval CRCs after negative testUnrehydrated gFOBT has low sensitivity for CRC detection (45% in the UK trial and 54% in the Danish trial). true positive rate50% (United Kingdom and Danish RCTs)false positive rate5%-10%true negative rate90%-95% (from observational studies as RCTs did not report specificity)false negative rate50%ES Table 1:Guaiac FOBT - GRADE Quality of Evidence for InterventionsOutcomeDesignQualityConsistencyDirectnessOverall QualityCRCMortalityRCTDanishN = 137,485United KingdomN = 152,850No seriouslimitationsYes (RR reduction in 2 trials13% and 16%; absolutedifference 0.1% and 0.2%respectively).Age rangeDanish and UnitedKingdom study 45-75yearsHighCRC indicates colorectal cancer; FOBT, fecal occult blood test; GRADE, Grading of Recommendations Assessment, Development and Evaluation; RCT, randomized controlled trial.*Unlikely to be an important uncertainty.ES Table 2:GRADE Quality of Evidence for Diagnostic Tests: Implications of Testing Focusing on AccuracyNew Test and Reference TestPutative BenefitDiagnostic AccuracyPatient Outcomes and Expected Impact on ManagementSensitivitySpecificityTrue PositiveTrue NegativeFalse PositiveFalse NegativePresumed Influence on Outcomes Important to PatientsiFOBT and ColonoscopySimple, non-invasiveLessLessBenefit from diagnosis and treatment after confirmatory colonoscopySmall risk of bowel perforation during colonoscopyBenefit of reassuranceAnxiety/worry leading up to confirmatory colonoscopySmall risk of bowel perforation during confirmatory colonoscopyDetriment from delayed diagnosisDirectness of Evidence (Test Results) for Outcomes Important to PatientsSome uncertainty (until after confirmatory colonoscopy)No UncertaintyUncertaintyUncertaintyFOBT indicates fecal occult blood test; GRADE, Grading of Recommendations Assessment, Development and Evaluation.Es Table 3:Immunochemical FOBT - GRADE Quality of Evidence for Diagnostic StudiesNo. ofStudiesDesignLimitationsIndirectnessInconsistencyImprecise dataQuality6Diagnostic cohort (single test)(reference standard for positive and negative iFOBT results was colonoscopy)No serious limitationsTP Some uncertaintyTN No uncertaintyFP UncertaintyFN UncertaintyTP rate = 69%TN rate = 94%FP rate = 6%FN rate = 30%(from direct comparison study)Diagnostic cohort iFOBT sensitivities: 50% to 90%High I(2)in pooled sensitivity and specificityWide range in confidence intervals in direct comparison studyLow*FN indicates false negative; FOBT, fecal occult blood test; FP, false positive; Development and Evaluation; TN, true negative; TP, true positive.*Uncertainty until after confirmatory colonoscopy†Stress/worry for patient until confirmatory colonoscopy‡Detrimental effects due to delayed diagnosis.§For these 3 reasons, downgrade quality from High to Moderate.║For these 3 reasons, downgrade quality from Moderate to Low. CONSIDERATIONS FOR THE ONTARIO HEALTH SYSTEM: Executive Summary Table 4 shows the potential system pressures and benefit/risk analysis for the use of FOBT and colonoscopy to screen for CRC in average-risk adults, ages 50 and over in Ontario. Es Table 4:Summary of Potential System Pressures for FOBT ScreeningCriterionColonoscopyFOBTPrimarily prevent or detect cancer?Prevent and detectDetectFrequency of screeningEvery 10 yearsMust repeat at regular intervalsEvery 2 yearsMust repeat at regular intervalsLevel of evidenceObservational studiesRCTsBenefitsUsed as gold standard in studiesINTERVENTION GRADE QUALITY: High (gFOBT)DIAGNOSTIC GRADE QUALITY: Low (iFOBT)No RCTs examining the effectiveness of repeated iFOBT on CRC mortality reduction were identifiedLimited direct/indirect evidence that iFOBT has superior sensitivity/specificity to unrehydrated gFOBT for detection of CRCRisks0.1% risk of serious bleeding and perforation requiring surgery0.3% risk of serious complications (stroke/bleeding requiring hospitalization/ myocardial infarction)High interval cancer rateThe small benefit in CRC mortality reduction (absolute difference 0.1% to 0.2%) also coincides with a 0.3% risk of serious complications.Preparation requirementsNo food 1 day prior to examOffice/hospital visitComplete bowel preparationSedationEliminate citrus fruit and juices and vitamin C from diet for 3 days prior to/during stool collection.Person applies 2 samples per bowel movement (each occurring on 3 different days) onto test areas of FOBT cards.Resources required for screening asymptomatic, average-risk adults ≥ 50 yearsIncreased demand for colonoscopies and colonoscopists or nurses who perform colonoscopies. 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Ont Health Technol Assess Ser · Jan 2009
Community-based care for the management of type 2 diabetes: an evidence-based analysis.
In June 2008, the Medical Advisory Secretariat began work on the Diabetes Strategy Evidence Project, an evidence-based review of the literature surrounding strategies for successful management and treatment of diabetes. This project came about when the Health System Strategy Division at the Ministry of Health and Long-Term Care subsequently asked the secretariat to provide an evidentiary platform for the Ministry's newly released Diabetes Strategy.After an initial review of the strategy and consultation with experts, the secretariat identified five key areas in which evidence was needed. Evidence-based analyses have been prepared for each of these five areas: insulin pumps, behavioural interventions, bariatric surgery, home telemonitoring, and community based care. For each area, an economic analysis was completed where appropriate and is described in a separate report.To review these titles within the Diabetes Strategy Evidence series, please visit the Medical Advisory Secretariat Web site, http://www.health.gov.on.ca/english/providers/program/mas/mas_about.html,DIABETES STRATEGY EVIDENCE PLATFORM: Summary of Evidence-Based AnalysesContinuous Subcutaneous Insulin Infusion Pumps for Type 1 and Type 2 Adult Diabetics: An Evidence-Based AnalysisBehavioural Interventions for Type 2 Diabetes: An Evidence-Based AnalysisBARIATRIC SURGERY FOR PEOPLE WITH DIABETES AND MORBID OBESITY: An Evidence-Based SummaryCommunity-Based Care for the Management of Type 2 Diabetes: An Evidence-Based AnalysisHome Telemonitoring for Type 2 Diabetes: An Evidence-Based AnalysisApplication of the Ontario Diabetes Economic Model (ODEM) to Determine the Cost-effectiveness and Budget Impact of Selected Type 2 Diabetes Interventions in Ontario ⋯ The initial search yielded 2,116 unique citations, from which 22 RCTs trials and nine systematic reviews published were identified as meeting the eligibility criteria. Of these, five studies focused on care provided by at least a nurse, dietician, and physician (primary care and/or specialist) model of care (Model 1; see Table ES 1), while three studies focused on care provided by at least a pharmacist and primary care physician (Model 2; see Table ES 2). Based on moderate quality evidence, specialized multidisciplinary community care Model 2 has demonstrated a statistically and clinically significant reduction in HbA1c of 1.0% compared with usual care. The effects of this model on SBP, however, are uncertain compared with usual care, based on very-low quality evidence. Specialized multidisciplinary community care Model 2 has demonstrated a statistically and clinically significant reduction in both HbA1c of 1.05% (based on high quality evidence) and SBP of 7.13 mm Hg (based on moderate quality evidence) compared to usual care. For both models, the evidence does not suggest a preferred setting of care delivery (i.e., primary care vs. hospital outpatient clinic vs. community clinic). Table ES1:Summary of Results of Meta-Analyses of the Effects of Multidisciplinary Care Model 1OutcomeEstimate of effect(95% CI)Heterogeneity I(2)(p-value)GRADEGlycosylated Hemoglobin (HbA1c [%])-1.00 [-1.27, -0.73]4% (p=0.37)Moderate-quality Subgroup: Moderate-to-High Quality-0.91 [-1.19, -0.62]0% (p=0.74)Systolic Blood Pressure (mm Hg)-2.04 [-13.80, 9.72]89% (p=0.002)Very-low quality*Mean change from baseline to follow-up between intervention and control groupsTable ES2:Summary of Results of Meta-Analyses of the Effects of Multidisciplinary Care Model 2OutcomeEstimate of effect(95% CI)Heterogeneity I(2)(p-value)GRADEGlycosylated Hemoglobin (HbA1c [%])-1.05 [-1.57, -0.52]0% (p=0.75)High-qualitySystolic Blood Pressure (mm Hg)-7.13 [-11.78, -2.48]46% (p=0.17)Moderate quality*Mean change from baseline to follow-up between intervention and control groups.
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Ont Health Technol Assess Ser · Jan 2009
Home telemonitoring for type 2 diabetes: an evidence-based analysis.
In June 2008, the Medical Advisory Secretariat began work on the Diabetes Strategy Evidence Project, an evidence-based review of the literature surrounding strategies for successful management and treatment of diabetes. This project came about when the Health System Strategy Division at the Ministry of Health and Long-Term Care subsequently asked the secretariat to provide an evidentiary platform for the Ministry's newly released Diabetes Strategy.After an initial review of the strategy and consultation with experts, the secretariat identified five key areas in which evidence was needed. Evidence-based analyses have been prepared for each of these five areas: insulin pumps, behavioural interventions, bariatric surgery, home telemonitoring, and community based care. For each area, an economic analysis was completed where appropriate and is described in a separate report.To review these titles within the Diabetes Strategy Evidence series, please visit the Medical Advisory Secretariat Web site, http://www.health.gov.on.ca/english/providers/program/mas/mas_about.html,DIABETES STRATEGY EVIDENCE PLATFORM: Summary of Evidence-Based AnalysesContinuous Subcutaneous Insulin Infusion Pumps for Type 1 and Type 2 Adult Diabetics: An Evidence-Based AnalysisBehavioural Interventions for Type 2 Diabetes: An Evidence-Based AnalysisBARIATRIC SURGERY FOR PEOPLE WITH DIABETES AND MORBID OBESITY: An Evidence-Based SummaryCommunity-Based Care for the Management of Type 2 Diabetes: An Evidence-Based AnalysisHome Telemonitoring for Type 2 Diabetes: An Evidence-Based AnalysisApplication of the Ontario Diabetes Economic Model (ODEM) to Determine the Cost-effectiveness and Budget Impact of Selected Type 2 Diabetes Interventions in Ontario ⋯ Based on low quality evidence, blood glucose home telemonitoring technologies confer a statistically significant reduction in HbA1c of ~0.50% in comparison to usual care when used adjunctively to a broader telemedicine initiative for adults with type 2 diabetes.Exploratory analysis suggests differences in effect sizes for the primary outcome when analyzing by subgroup; however, this should only be viewed as exploratory or hypothesis-generating only.Significant limitations and/or sources of clinical heterogeneity are present in the available literature, generating great uncertainty in conclusions.More robust trials in type 2 diabetics only, utilizing more modern technologies, preferably performed in an Ontario or a similar setting (given the infrastructure demands and that the standard comparator is usual care), while separating out the effects of other telemedicine intervention components, are needed to clarify the effect of emerging remote blood glucose monitoring technologies.
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Ont Health Technol Assess Ser · Jan 2009
Management of chronic pressure ulcers: an evidence-based analysis.
In April 2008, the Medical Advisory Secretariat began an evidence-based review of the literature concerning pressure ulcers.Please visit the Medical Advisory Secretariat Web site, http://www.health.gov.on.ca/english/providers/program/mas/tech/tech_mn.html to review these titles that are currently available within the Pressure Ulcers series.PRESSURE ULCER PREVENTION: an evidence based analysisThe cost-effectiveness of prevention strategies for pressure ulcers in long-term care homes in Ontario: projections of the Ontario Pressure Ulcer Model (field evaluation)MANAGEMENT OF CHRONIC PRESSURE ULCERS: an evidence-based analysis ⋯ Findings from the analysis of the included studies are summarized below: CLEANSING: There is no good trial evidence to support the use of any particular wound cleansing solution or technique for pressure ulcers. DEBRIDEMENT: There was no evidence that debridement using collagenase, dextranomer, cadexomer iodine, or maggots significantly improved complete healing compared with placebo.There were no statistically significant differences between enzymatic or mechanical debridement agents with the following exceptions:Papain urea resulted in better debridement than collagenase.Calcium alginate resulted in a greater reduction in ulcer size compared to dextranomer.Adding streptokinase/streptodornase to hydrogel resulted in faster debridement.Maggot debridement resulted in more complete debridement than conventional treatment.There is limited evidence on the healing effects of debridement devices. DRESSINGS: Hydrocolloid dressing was associated with almost three-times more complete healing compared with saline gauze. There is evidence that hydrogel and hydropolymer may be associated with 50% to 70% more complete healing of pressure ulcers than hydrocolloid dressing.No statistically significant differences in complete healing were detected among other modern dressings.There is evidence that polyurethane foam dressings and hydrocellular dressings are more absorbent and easier to remove than hydrocolloid dressings in ulcers with moderate to high exudates.In deeper ulcers (stage III and IV), the use of alginate with hydrocolloid resulted in significantly greater reduction in the size of the ulcers compared to hydrocolloid alone.Studies on sustained silver-releasing dressing demonstrated a tendency for reducing the risk of infection and promoting faster healing, but the sample sizes were too small for statistical analysis or for drawing conclusions. BIOLOGICAL THERAPIES: The efficacy of platelet-derived growth factors (PDGFs), fibroblast growth factor, and granulocyte-macrophage colony stimulating factor in improving complete healing of chronic pressure ulcers has not been established.Presently only Regranex, a recombinant PDGF, has been approved by Health Canada and only for treatment of diabetic ulcers in the lower extremities.A March 2008 US Food and Drug Administration (FDA) communication reported increased deaths from cancers in people given three or more prescriptions for Regranex.Limited low-quality evidence on skin matrix and engineered skin equivalent suggests a potential role for these products in healing refractory advanced chronic pressure ulcers, but the evidence is insufficient to draw a conclusion. ADJUNCTIVE PHYSICAL THERAPY: There is evidence that electrical stimulation may result in a significantly greater reduction in the surface area and more complete healing of stage II to IV ulcers compared with sham therapy. No conclusion on the efficacy of electrotherapy can be drawn because of significant statistical heterogeneity, small sample sizes, and methodological flaws.The efficacy of other adjunctive physical therapies [electromagnetic therapy, low-level laser (LLL) therapy, ultrasound therapy, ultraviolet light therapy, and negative pressure therapy] in improving complete closure of pressure ulcers has not been established. NUTRITION THERAPY: Supplementation with 15 grams of hydrolyzed protein 3 times daily did not affect complete healing but resulted in a 2-fold improvement in Pressure Ulcer Scale for Healing (PUSH) score compared with placebo.Supplementation with 200 mg of zinc three times per day did not have any significant impact on the healing of pressure ulcers compared with a placebo.Supplementation of 500 mg ascorbic acid twice daily was associated with a significantly greater decrease in the size of the ulcer compared with a placebo but did not have any significant impact on healing when compared with supplementation of 10 mg ascorbic acid three times daily.A very high protein tube feeding (25% of energy as protein) resulted in a greater reduction in ulcer area in institutionalized tube-fed patients compared with a high protein tube feeding (16% of energy as protein).Multinutrient supplements that contain zinc, arginine, and vitamin C were associated with a greater reduction in the area of the ulcers compared with standard hospital diet or to a standard supplement without zinc, arginine, or vitamin C.Firm conclusions cannot be drawn because of methodological flaws and small sample sizes. MULTIDISCIPLINARY WOUND CARE TEAMS: The only RCT suggests that multidisciplinary wound care teams may significantly improve healing in the acute care setting in 8 weeks and may significantly shorten the length of hospitalization. However, since only an abstract is available, study biases cannot be assessed and no conclusions can be drawn on the quality of this evidence.
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Ont Health Technol Assess Ser · Jan 2009
Continuous Subcutaneous Insulin Infusion (CSII) Pumps for Type 1 and Type 2 Adult Diabetic Populations: An Evidence-Based Analysis.
In June 2008, the Medical Advisory Secretariat began work on the Diabetes Strategy Evidence Project, an evidence-based review of the literature surrounding strategies for successful management and treatment of diabetes. This project came about when the Health System Strategy Division at the Ministry of Health and Long-Term Care subsequently asked the secretariat to provide an evidentiary platform for the Ministry's newly released Diabetes Strategy.After an initial review of the strategy and consultation with experts, the secretariat identified five key areas in which evidence was needed. Evidence-based analyses have been prepared for each of these five areas: insulin pumps, behavioural interventions, bariatric surgery, home telemonitoring, and community based care. For each area, an economic analysis was completed where appropriate and is described in a separate report.To review these titles within the Diabetes Strategy Evidence series, please visit the Medical Advisory Secretariat Web site, http://www.health.gov.on.ca/english/providers/program/mas/mas_about.html,DIABETES STRATEGY EVIDENCE PLATFORM: Summary of Evidence-Based AnalysesContinuous Subcutaneous Insulin Infusion Pumps for Type 1 and Type 2 Adult Diabetics: An Evidence-Based AnalysisBehavioural Interventions for Type 2 Diabetes: An Evidence-Based AnalysisBARIATRIC SURGERY FOR PEOPLE WITH DIABETES AND MORBID OBESITY: An Evidence-Based SummaryCommunity-Based Care for the Management of Type 2 Diabetes: An Evidence-Based AnalysisHome Telemonitoring for Type 2 Diabetes: An Evidence-Based AnalysisApplication of the Ontario Diabetes Economic Model (ODEM) to Determine the Cost-effectiveness and Budget Impact of Selected Type 2 Diabetes Interventions in Ontario ⋯ The database search identified 519 relevant citations published between 1996 and March 24, 2009. Of the 519 abstracts reviewed, four RCTs and one abstract met the inclusion criteria outlined above. While efficacy outcomes were reported in each of the trials, a meta-analysis was not possible due to missing data around standard deviations of change values as well as missing data for the first period of the crossover arm of the trial. Meta-analysis was not possible on other outcomes (quality of life, insulin requirements, frequency of hypoglycemia) due to differences in reporting. HBA1C: In studies where no baseline data was reported, the final values were used. Two studies (Hanaire-Broutin et al. 2000, Hoogma et al. 2005) reported a slight reduction in HbA1c of 0.35% and 0.22% respectively for CSII pumps in comparison to MDI. A slightly larger reduction in HbA1c of 0.84% was reported by DeVries et al.; however, this study was the only study to include patients with poor glycemic control marked by higher baseline HbA1c levels. One study (Bruttomesso et al. 2008) showed no difference between CSII pumps and MDI on Hba1c levels and was the only study using insulin glargine (consistent with results of parallel RCT in abstract by Bolli 2004). While there is statistically significant reduction in HbA1c in three of four trials, there is no evidence to suggest these results are clinically significant. MEAN BLOOD GLUCOSE: Three of four studies reported a statistically significant reduction in the mean daily blood glucose for patients using CSII pump, though these results were not clinically significant. One study (DeVries et al. 2002) did not report study data on mean blood glucose but noted that the differences were not statistically significant. There is difficulty with interpreting study findings as blood glucose was measured differently across studies. Three of four studies used a glucose diary, while one study used a memory meter. In addition, frequency of self monitoring of blood glucose (SMBG) varied from four to nine times per day. Measurements used to determine differences in mean daily blood glucose between the CSII pump group and MDI group at clinic visits were collected at varying time points. Two studies use measurements from the last day prior to the final visit (Hoogma et al. 2005, DeVries et al. 2002), while one study used measurements taken during the last 30 days and another study used measurements taken during the 14 days prior to the final visit of each treatment period. GLUCOSE VARIABILITY: All four studies showed a statistically significant reduction in glucose variability for patients using CSII pumps compared to those using MDI, though one, Bruttomesso et al. 2008, only showed a significant reduction at the morning time point. Brutomesso et al. (ABSTRACT TRUNCATED)