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PubMed1978

Color context as a factor in encoding and as an organization device for retrieval of word lists.

One hundred twenty female undergraduates were presented hierarchically organized or randomly arranged word lists within a context of hierarchically organized or randomly arranged color patterns. Recall scores were significantly higher with a hierarchic color pattern than with a random color pattern; this facilitating effect occurred for both hierarchic organizations and random arrangements of the word lists. The results suggest that Ss may use context as both a cueing of differentiating factor in encoding and as an organizational device for retrieval.

Color Perception↗

PubMed2006

The natural history of new orthopaedic devices.

Each year, hundreds of new devices and implants are introduced for orthopaedic surgeons. However, the proportion of new devices which ultimately will be successful is unknown. We investigated the natural history of new devices introduced to the orthopaedic market. From a list of all devices approved for use by the Food & Drug Administration 5 and 10 years before, a cohort of 100 devices was randomly selected using a random number list. Companies were contacted regarding the safety record and current availability of these devices. The company response rate was 93%. Forty-seven percent of devices approved 10 years ago and 25% of devices approved 5 years ago no longer were on the market. Of the 55 companies studied, 18 (33%) were out of business and their devices no longer were available. Devices approved 10 years ago were more likely to be unavailable than devices approved 5 years ago. Devices introduced by smaller companies were more likely to be unavailable. The majority of unavailable devices were discontinued not for clinical problems, but for poor market performance. Only 2% of devices studied had safety problems. Approximately 50% of devices approved for introduction to the orthopaedic marketplace no longer are available 10 years later. However, major device-related problems seem uncommon.

Device Approval↗

PubMed1998

The Delphi list: a criteria list for quality assessment of randomized clinical trials for conducting systematic reviews developed by Delphi consensus.

Most systematic reviews rely substantially on the assessment of the methodological quality of the individual trials. The aim of this study was to obtain consensus among experts about a set of generic core items for quality assessment of randomized clinical trials (RCTs). The invited participants were experts in the field of quality assessment of RCTs. The initial item pool contained all items from existing criteria lists. Subsequently, we reduced the number of items by using the Delphi consensus technique. Each Delphi round comprised a questionnaire, an analysis, and a feedback report. The feedback report included staff team decisions made on the basis of the analysis and their justification. A total of 33 international experts agreed to participate, of whom 21 completed all questionnaires. The initial item pool of 206 items was reduced to 9 items in three Delphi rounds. The final criteria list (the Delphi list) was satisfactory to all participants. It is a starting point on the way to a minimum reference standard for RCTs on many different research topics. This list is not intended to replace, but rather to be used alongside, existing criteria lists.

Delphi Technique↗

PubMed2006

Does sampling using random digit dialling really cost more than sampling from telephone directories: debunking the myths.

BACKGROUND: Computer assisted telephone interviewing (CATI) is widely used for health surveys. The advantages of CATI over face-to-face interviewing are timeliness and cost reduction to achieve the same sample size and geographical coverage. Two major CATI sampling procedures are used: sampling directly from the electronic white pages (EWP) telephone directory and list assisted random digit dialling (LA-RDD) sampling. EWP sampling covers telephone numbers of households listed in the printed white pages. LA-RDD sampling has a better coverage of households than EWP sampling but is considered to be more expensive due to interviewers dialling more out-of-scope numbers. METHODS: This study compared an EWP sample and a LA-RDD sample from the New South Wales Population Health Survey in 2003 on demographic profiles, health estimates, coefficients of variation in weights, design effects on estimates, and cost effectiveness, on the basis of achieving the same level of precision of estimates. RESULTS: The LA-RDD sample better represented the population than the EWP sample, with a coefficient of variation of weights of 1.03 for LA-RDD compared with 1.21 for EWP, and average design effects of 2.00 for LA-RDD compared with 2.38 for EWP. Also, a LA-RDD sample can save up to 14.2% in cost compared to an EWP sample to achieve the same precision for health estimates. CONCLUSION: A LA-RDD sample better represents the population, which potentially leads to reduced bias in health estimates, and rather than costing more than EWP actually costs less.

Adolescent↗

PubMed1987

A microcomputer program for the generation of random grid squares in quantitative analysis.

Subjectivity in selecting random grid squares for routine quantitative analysis can be circumvented through a combination of finder grids and a computer program. The simple BASIC program described in this paper generates a list of random grid-square numbers, which are sequentially analyzed. The concept was applied in the quantitation of asbestos and other microparticles in environmental samples. The use of finder grids and this program can also be useful in quality-control programs and in cross-referencing analyses, as well as in the study of biological specimens.

Asbestos↗

PubMed1995

Use of Spanish surnames to identify Latinos: comparison to self-identification.

Difficulties in identification of Latinos from secondary datasets have often been addressed by the use of a Spanish surname list. To evaluate the sensitivity and specificity of the 1980 U.S. Census Spanish surname list in correctly identifying Latino ethnicity, we conducted a cross-sectional survey of adult members of a prepaid health plan in the San Francisco Bay Area. We compared a randomly selected list of 1345 Spanish surnames and 717 non-Spanish surnames from health plan membership lists with their self-identified race and ethnicity obtained by telephone interviews. The sample was stratified according to surname group (Spanish or non-Spanish), sex, age, and county. Compared with self-identified ethnicity, a Spanish surname was 88.4% sensitive in identifying Latino men and 70.4% sensitive in identifying Latina women. The non-Spanish surname list was 94.1% sensitive and 95.0% specific in correctly identifying non-Latinos. Although the overall negative predictive value was 97.8%, the positive predictive value of a Spanish surname was only 68.3% for men and 55.7% for women. The low positive predictive value was largely due to the 316 (61%) Filipinos among the 517 persons with Spanish surnames who were not Latinos. We conclude that the use of the Spanish surname list alone to ascertain race and ethnicity in the San Francisco Bay Area both falsely identifies a large number of non-Latino persons as Latino and fails to identify a small proportion of Latinos. Although the level of sensitivity and specificity for Spanish surnames will vary with the area under study, this source of inaccuracy must be considered in studies that plan to use data based on Spanish surnames.

Adult↗

PubMed1994

A randomized double-blinded comparison of the antiemetic efficacy of ondansetron and droperidol in patients receiving high-dose interleukin-2.

Emesis and nausea are common toxicities seen during high-dose interleukin-2 (IL-2) therapy (720,000 IU/kg i.v. every 8 h). A growing list of randomized studies have documented the efficacy of ondansetron, a potent antagonist of the 5-hydroxytryptamine3 receptor, in preventing acute chemotherapy-induced emesis and nausea. However, no study has evaluated the efficacy of ondansetron in preventing IL-2-induced emesis and nausea. This double-blinded, randomized trial was performed to compare the antiemetic and antinausea efficacy of ondansetron with that of droperidol, a butyrophenone, in patients receiving high-dose IL-2 on protocols at the National Cancer Institute. Ondansetron or droperidol was given intravenously, 30 min prior to the first dose of IL-2 and then every 8 h for the duration of IL-2 treatment. No significant differences were seen between the two agents in complete freedom from emesis (p2 = 0.51), level of nausea (p2 = 0.17), antiemetic treatment failure (p2 = 0.89), and time to first emetic episode (p2 = 0.44). Equivalent doses of IL-2 were administered on each arm of the study, with a similar incidence of liver dysfunction (p2 = 0.15) and diarrhea (p2 = 0.64). Finally, there was no significant difference in the response rates to metastatic disease in either arm of the antiemetic study (p2 = 0.67), and these response rates were similar to those in other patients treated under immunotherapy protocols in the Surgery Branch of the National Cancer Institute with high-dose IL-2. We conclude that droperidol is equally effective in preventing emesis and controlling nausea when compared with ondansetron for patients receiving high-dose IL-2.

Adult↗

PubMed1996

Prevalence and treatment of chronic airways obstruction in adults over the age of 45.

BACKGROUND: Chronic airways obstruction is common in adults and the elderly. To investigate the possibility that older adults with obstructive airways disease frequently do not receive appropriate treatment, the respiratory symptoms, medication use, and pulmonary function were studied in a random sample of white adults aged over 45 living in central Manchester, UK. METHODS: A postal questionnaire survey was performed on 783 men and women aged 45 years and over selected from GP lists by random number tables. Subjects completing the questionnaire were invited to attend for pulmonary function testing and methacholine challenge (Newcastle dosimeter method). RESULTS: The questionnaire response rate was 92.3% (723 subjects). The mean age of the population was 66.1 years and 57.2% were women; 29.2% were current smokers and 37.3% were ex-smokers. Asthma or bronchitis was reported by 30.0%. Two hundred and forty seven representative subjects attended for pulmonary function testing and spirometric evidence of chronic airways obstruction was found in 26.4%. Respiratory symptoms were reported by 76.6% of subjects with chronic airways obstruction; 55.0% had features which may predict potential improvement on treatment (increased non-specific bronchial responsiveness or significant bronchodilator reversibility). However, only 55.4% of subjects with airways obstruction had received a diagnosis of asthma or chronic bronchitis and only 36.9% were using inhaled bronchodilators or steroids. CONCLUSIONS: Chronic airways obstruction is very common in adults in this inner city population, but is frequently overlooked. Most subjects with chronic airways obstruction are not receiving appropriate treatment.

Aged↗

PubMed1981

Practice effects for normal listeners' performance on a nonsense syllable test.

Each of 4 groups (N: 5) of normal-hearing young adults responded to the consonant-vowel-consonant-vowel Nonsense Syllable Test (Edgerton and Danhauer, 1979). Groups I and II on any one day for 5 consecutive days received one presentation of both Lists A and B at 16 and at 56 db re individual SRT, with (Group II) or without (Group I) visual reinforcement as to the correctness of the response. Groups III and IV received 15 randomizations of List A (non-reinforced) in a single session at 16 or 56 db SL, respectively. S's were tested individually diotically; verbal responses were phonetically transcribed using both audio and visual cues, and were scored phonetically. There were no significant differences in means between Groups I vs II as a result of reinforcement, but differences were noted in both groups for presentation levels and trials (days). No practice effects were noted in Groups III and IV. The NST may be used for multiple administrations within a single session, as in deriving performance-intensity functions, or in hearing aid evaluations, without biases due to practice.

Adult↗

PubMed2000

Cisapride treatment for gastro-oesophageal reflux in children: a systematic review of randomized controlled trials.

The aim of the systematic review was to determine the effect of cisapride compared with placebo or other non-surgical therapies for the treatment of symptoms of gastro-oesophageal reflux in children. We searched MEDLINE, EMBASE, the Cochrane Controlled Trials Register, Science Citation Index and reference lists for randomized controlled trials which compared cisapride with placebo or other non-surgical therapy in children. We included only trials which reported reflux-related symptoms as an outcome, provided that cisapride was administered orally for at least I week. Seven trials (286 children in total) compared cisapride with placebo. Two trials reported good concealment of treatment allocation. The pooled odds ratio for the 'same or worse' symptoms was 0.34 (95% CI 0.10, 1.19). There was substantial heterogeneity between studies (P < 0.00001) and the funnel plot was asymmetrical. Adverse effects (mainly diarrhoea) were not significantly increased with cisapride (pooled odds ratio (OR) 1.80: 0.87, 3.70). The reflux index was significantly reduced in children treated with cisapride (weighted mean difference -6.49: -10.13, -2.85). One study (50 children) compared cisapride with gaviscon plus carobel: the OR for the 'same or worse' symptoms was 3.26 (0.93, 11.38). There was no clear evidence that cisapride reduced symptoms of gastro-oesophageal reflux. As smaller, poorer quality studies were biased in favour of a positive treatment effect, the pooled OR overestimated the potential benefits of cisapride. There was some evidence to suggest that gaviscon plus carobel may be a more effective option than cisapride.

Child↗

PubMed2001

Occlusal stabilization appliances. Evidence of their efficacy.

BACKGROUND: There is substantial controversy regarding the value of occlusal appliances for managing temporomandibular joint disorders. This article specifically assesses whether the evidence is sufficient to judge occlusal appliances as being efficacious for the management of localized masticatory myalgia, arthralgia or both. A major confounder is that few studies have measured or evaluated whether subjects had strong, ongoing parafunctional activity (such as clenching or grinding) and whether appliances influenced this behavior. LITERATURE REVIEWED: The authors evaluated four placebo-controlled studies, several randomized wait-list controlled studies and several random-assignment treatment-comparison studies. Data from the wait-list condition studies vs. those from the occlusal appliance condition studies consistently suggested that the latter treatment's effect on patient symptom level is far more than that of no treatment on a wait-list group's condition. In contrast, the studies on placebo-controlled vs. occlusal appliance studies yielded a mix of data: two showed a positive benefit of occlusal vs. nonoccluding appliances, and two showed a null effect or no difference. CONCLUSIONS: Considering all of the available data (pro and con), the authors conclude that the use of occlusal appliances in managing localized masticatory myalgia, arthralgia or both is sufficiently supported by evidence in the literature. CLINICAL IMPLICATIONS: The mechanism of action by which occlusal appliances affect localized myalgia and arthralgia probably is behavioral modification of jaw clenching. However, if the behavior continues unabated, even the best splint will not work.

Arthralgia↗

PubMed2005

The effect of an educational program to improve health-related quality of life in patients with osteoarthritis on waiting list for total knee replacement: a randomized study.

OBJECTIVE: To evaluate the effect of therapeutic education and functional readaptation (TEFR) on health-related quality of life (HRQL) in patients diagnosed with osteoarthritis on a waiting list for total knee replacement (TKR). METHODS: Randomized controlled trial of 9 months duration was conducted. One hundred consecutive outpatients (71 females, mean age 71 years (range 50-86), mean disease duration 11.84+/-10.52 months) were included. Patients were randomized in two groups. The intervention group received TEFR added to conventional (pharmacological) treatment (n=51). The control group received conventional (pharmacological) treatment only (n=49). The main outcome variable was self-reported HRQL measured by the Spanish version of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Secondary outcomes were general HRQL measured by Short Form Health Survey general questionnaire (SF-36), number of visits to general physicians and their cost. Assessments were done at baseline and at 9 months. MAIN RESULTS: Eighty patients completed the study. Significant improvement in the WOMAC function was found at 9 months in the TERF group with respect to the control group (P=0.035). Consumption of analgesics increased significantly in the TERF group compared with controls (P=0.036). Significant improvements in pain (P=0.027) measured by WOMAC and in bodily pain (P=0.043) and physical function (P=0.031), measured by SF-36, were observed in the intervention group with respect to baseline. CONCLUSIONS: The function dimension measured by WOMAC of patients who received both pharmacological treatment and TERF improved with respect to the control group receiving only pharmacological treatment. This suggests that a program of TEFR during the period on the waiting list for TKR may reduce the negative impact of this situation.

Aged↗

PubMed2002

A pilot study of the tolerability and efficacy of antiviral therapy in hepatitis C virus-infected patients awaiting liver transplantation.

Decompensated liver disease associated with chronic hepatitis C virus (HCV) infection is the most common indication for liver transplantation. It was shown previously that greater pretransplantation HCV titers are associated with relatively poor patient and graft survival. The tolerability and efficacy of antiviral therapy in patients with decompensated liver disease are not known. We conducted a pilot study to determine the likely tolerability and efficacy of pretransplantation antiviral therapy with interferon alfa-2b, with or without ribavirin. HCV RNA-positive patients at or near the top of their respective waiting lists were randomly assigned to one of three treatment regimens until the time of liver transplantation: (1) group A, interferon alfa-2b, 1 x 10(6) U/d; (2) group B, interferon alfa-2b, 3 x 10(6) U three times weekly; or (3) group C, interferon alfa-2b, 1 x 10(6) U/d, plus ribavirin, 400 mg twice daily. Less than half the patients screened met entry criteria, with thrombocytopenia and leukopenia the most common reasons for exclusion. Fifteen patients were administered antiviral therapy; three patients in group A and six patients each in groups B and C. Loss of detectable HCV RNA was seen in 33% of patients, whereas 55% had a decrease in viral titers on therapy. Twenty-three adverse events occurred, including 20 serious adverse events. Thrombocytopenia was the most common adverse event. Two infectious complications occurred; one of these had a fatal outcome. We conclude that although pretransplantation antiviral therapy may reduce HCV titers in a minority of patients who meet treatment initiation criteria, adverse events associated with therapy are frequent and often severe in patients with Child's class B and C cirrhosis.

Antiviral Agents↗

PubMed2003

Memory for actions: item and relational information in categorized lists.

Enacting action phrases in subject-performed tasks (SPTs) leads to better free recall than hearing or reading the same materials in verbal tasks (VTs). This enactment effect is usually explained by better item-specific information in SPTs than in VTs. The role of relational information is controversial. In the present paper, we will take the multiple recall approach to study the role of item and relational information in memory for actions by computing the number of item gains and the number of item losses over trials. This approach has previously been applied to lists of unrelated action phrases. We applied it to categorically related lists, also allowing a measure of relational information by clustering scores. It was found that SPTs produced more item gains than VTs. This finding confirmed the assumption that SPTs provide better item-specific information than VTs. The number of item losses did not differ between VTs and SPTs. This finding suggests that relational information is equally provided by VTs and SPTs. However, the organizational scores showed a more differentiated picture. Clustering was greater in SPTs than in VTs with randomly presented lists, but not with blocked lists. We suggested that these results, as well as other findings from the literature, could be explained by distinguishing automatic and strategic processes and the types of item associations that are addressed by these processes.

Attention↗

PubMed2004

[Evidence based surgery of cancer of head of pancreas].

Physicians and surgeons who treat patients with gastrointestinal or hepatic disease must prescribe the most appropriate diagnostic tests, together with an accurate prognosis and effective and safe therapy. This paper examines the best modalities of surgical treatment for cancer of the pancreas, in an evidence-based approach. Evidence was classified as follows: Grade A : evidence from large randomized controlled trials (RCT) or systematic reviews (including meta-analyses) of multiple randomized trials which collectively have at least as much data as one single well-defined trial. Grade B: evidence from at least one high-quality study of non-randomized cohorts or evidence from at least one high-quality case-control study or one high-quality case series. Grade C: opinions from experts without references or access to any of the foregoing The data were obtained from Medline and from controlled randomized trials listed in the Cochrane Library up to the end of 2003. Two series (grade B) showed the superiority of Whipple over total pancreatectomy, with respective median survival times of 12.6 months and 9.6 months. Extensive lymphadenectomy (grade A) in patients with positive lymph nodes gave significantly better survival than standard resection in one trial, but this was not confirmed in the other trial. Results of pylorus-preserving pancreaticoduodenectomy (PPPD) were not different from those of the Whipple procedure on postoperative mortality, morbidity or survival (grade A). Portal vein resection increased the resectability rate. Post-operative mortality was not increased: survival was not different in four studies and was shorter in another four studies (grade C). Low-dose postoperative erythromycin accelerates gastric emptying if the right gastric artery is preserved (grade A). One trial suggests that pancreaticogastrostomy reduces the risk of pancreatic fistula. The two other trials are controversial and showed no difference. One prospective non randomized study showed that stenting in pancreaticojejunostomy reduces the risk of pancreatic fistulae and intraabdominal abscess. To prevent this risk of pancreatic fistula, six controlled trials involving patients receiving octreotride were performed Three European trials showed a smaller volume of abdominal drainage fluid and an abnormal amylase concentration; however, two American trials failed to demonstrate a significant difference. Occlusion of the pancreatic duct with fibrin glue did not reduce the risk of pancreatic fistula, but increased the risk of developing diabetes. Intraabdominal drainage after pancreatic resection significantly increased post-operative complications (grade A). Surgical resection and reconstruction procedures for pancreatic cancer must be based on evidence-based studies. However, the most important prognostic factor is the surgeon's experience, not only with regard to the post-operative course, but also survival. Specific teaching and training is thus essential.

Evidence-Based Medicine↗

PubMed1995

Evaluation of a prototype esophageal detection device.

OBJECTIVE: To determine the ability of a prototype esophageal detection device (EDD) to identify esophageal misplacement of an endotracheal (ET) tube. METHODS: A prospective, randomized, blinded study of detection of esophageal intubation was conducted using 51 elective surgical patients who met inclusion criteria. A squeeze-bulb aspirator that creates a negative pressure of -80 to -90 torr was used for detection of esophageal intubation. The bulb should reinflate rapidly if the tube is in the noncollapsible trachea, but should not reinflate if the tube is in the collapsible esophagus. Each patient was prepared for surgery in the usual manner. The anesthesiologist placed an ET tube into the trachea. An identical tube was advanced the same distance into the esophagus. The tubes were labeled "A" or "B" according to a computer-generated random number list. An evaluator, who was blinded to the placement of the tubes, assessed one tube with the EDD. For most patients, a second evaluator, who was blinded to both tube placement and the results of the first evaluator, assessed the other tube. During evaluation, the tube cuffs were deflated. After data collection, the esophageal tube was removed and surgery was completed. RESULTS: All 45 esophageal tube placements were correctly identified. Thirty-five of the 40 ET tubes were correctly identified. Of the five ET tubes mislabeled, three were found in a mainstem bronchus. All had delayed bulb re-expansion. CONCLUSION: This prototype EDD is a useful method of identifying esophageal misplacement of an ET tube in anesthetized adult surgical patients.

Adolescent↗

PubMed1995

Strenuous physical activity in young adulthood and risk of breast cancer (United States).

The epidemiologic data on the relation between strenuous physical activity and breast cancer are limited and inconsistent. Because risk of breast cancer may be influenced by ovarian function which, in turn is modulated by physical activity, the hypothesis that exercise may be associated with a reduced risk of breast cancer merits further investigation. We, therefore, conducted a large case-control study in 1988-1991, and interviewed 6,888 women (17 to 74 years of age) with breast cancer in Maine, Massachusetts, New Hampshire, and Wisconsin (United States). Interviewed controls (9,539 women, 18 to 74 years of age) were selected randomly from lists of licensed drivers (for younger women) or from a roster of Medicare enrollees (for older women). We used multivariate adjusted odds ratios (OR) and 95 percent confidence intervals (CI) from logistic regression models to estimate relative risks between self-reported physical activity when 14 to 22 years of age and breast cancer. When compared with sedentary controls, women who reported any strenuous physical during ages 14 to 22 years had a modest reduction in the risk of breast cancer (OR = 0.95, CI = 0.93-0.97). However, those who exercised vigorously at least once a day had a 50 percent reduction in risk of breast cancer (OR = 0.5, CI = 0.4-0.7). These data support the hypothesis that women who are physically active have a reduced risk of breast cancer.

Adolescent↗

PubMedDate not supplied

Patients' interpretations of probability terms.

STUDY OBJECTIVES: To assess the meaning ascribed by patients to qualitative expressions of probability commonly used in medical care and to determine patient preferences for obtaining information when communicating with their physicians about medical risk numerically and/or qualitatively. DESIGN: Cross-sectional survey of consecutive patients. SETTING: A university-based Department of Veterans Affairs medical center. PARTICIPANTS: 133 patients sequentially seen in a general medicine clinic. MEASUREMENTS AND MAIN RESULTS: Subjects were given a randomly ordered list of 12 common terms, each a qualitative expression of probability. They were asked to indicate what they understood to be the numerical meaning of each word. The patients' probability estimates were found to comprise two groups of five terms each, with high intercorrelations among the probabilities assigned to the terms in each group. Mean probabilities assigned to terms in the first group all were greater than 60%, and mean probabilities assigned to terms in the second group all were below 50%. When asked whether they wanted chance information to be provided in numerical or qualitative terms, 32% reported that they wanted it only numerically; 35.3% wanted it only qualitatively; 21.8% wanted the information either way; and 8.3% wanted the information both ways. CONCLUSIONS: The numerical meanings that patients ascribe to probability terms fall into identifiable patterns. While patients vary in the actual values they assign to terms, the relative meanings of terms show consistent trends.

Analysis of Variance↗