Showing papers on "Clinical prediction rule published in 2005"

Derivation and Validation of a Prognostic Model for Pulmonary Embolism

Abstract: Rationale: An objective and simple prognostic model for patients with pulmonary embolism could be helpful in guiding initial intensity of treatment.Objectives: To develop a clinical prediction rule that accurately classifies patients with pulmonary embolism into categories of increasing risk of mortality and other adverse medical outcomes.Methods: We randomly allocated 15,531 inpatient discharges with pulmonary embolism from 186 Pennsylvania hospitals to derivation (67%) and internal validation (33%) samples. We derived our prediction rule using logistic regression with 30-day mortality as the primary outcome, and patient demographic and clinical data routinely available at presentation as potential predictor variables. We externally validated the rule in 221 inpatients with pulmonary embolism from Switzerland and France.Measurements: We compared mortality and nonfatal adverse medical outcomes across the derivation and two validation samples.Main Results: The prediction rule is based on 11 simple patient ...

Rules for identifying patients at increased risk for candidal infections in the surgical intensive care unit: approach to developing practical criteria for systematic use in antifungal prophylaxis trials.

Abstract: The high rates of invasive candidiasis among intensive care unit (ICU) patients suggest that antifungal prophylaxis might be of value, but rules identifying patients who would best benefit are not established. Based on a retrospective study of 327 patients who stayed in a surgical ICU for > or = 4 days and had an 11.0% rate of invasive candidiasis, we sought to identify useful predictive rules. As prior work suggests that prompt initiation of prophylaxis is of value, we required our rules to be based on patient data routinely available during the week prior to ICU admission through the third day of the ICU stay. Patients with any combination of diabetes mellitus, new onset hemodialysis, use of total parenteral nutrition, or receipt of broad-spectrum antibiotics had an invasive candidiasis rate of 16.6% versus a 5.1% rate for patients lacking these characteristics (P = 0.001). Fifty-two percent of patients staying > or = 4 days in the ICU met this rule and the rule captured 78% of the patients who eventually developed invasive candidiasis. Risk-stratified antifungal prophylaxis in the ICU is possible. Validation of these results in other types of ICU is now needed.

A clinical return-to-work rule for patients with back pain

Abstract: Background: Tools for early identification of workers with back pain who are at high risk of adverse occupational outcome would help concentrate clinical attention on the patients who need it most, while helping reduce unnecessary interventions (and costs) among the others. This study was conducted to develop and validate clinical rules to predict the 2-year work disability status of people consulting for nonspecific back pain in primary care settings. Methods: This was a 2-year prospective cohort study conducted in 7 primary care settings in the Quebec City area. The study enrolled 1007 workers (participation, 68.4% of potential participants expected to be eligible) aged 18–64 years who consulted for nonspecific back pain associated with at least 1 day9s absence from work. The majority (86%) completed 5 telephone interviews documenting a large array of variables. Clinical information was abstracted from the medical files. The outcome measure was “return to work in good health” at 2 years, a variable that combined patients9 occupational status, functional limitations and recurrences of work absence. Predictive models of 2-year outcome were developed with a recursive partitioning approach on a 40% random sample of our study subjects, then validated on the rest. Results: The best predictive model included 7 baseline variables (patient9s recovery expectations, radiating pain, previous back surgery, pain intensity, frequent change of position because of back pain, irritability and bad temper, and difficulty sleeping) and was particularly efficient at identifying patients with no adverse occupational outcome (negative predictive value 78%– 94%). Interpretation: A clinical prediction rule accurately identified a large proportion of workers with back pain consulting in a primary care setting who were at a low risk of an adverse occupational outcome.

Pragmatic application of a clinical prediction rule in primary care to identify patients with low back pain with a good prognosis following a brief spinal manipulation intervention

Abstract: Patients with low back pain are frequently encountered in primary care. Although a specific diagnosis cannot be made for most patients, it is likely that sub-groups exist within the larger entity of nonspecific low back pain. One sub-group that has been identified is patients who respond rapidly to spinal manipulation. The purpose of this study was to examine the association between two factors (duration and distribution of symptoms) and prognosis following a spinal manipulation intervention. Data were taken from two previously published studies. Patients with low back pain underwent a standardized examination, including assessment of duration of the current symptoms in days, and the distal-most distribution of symptoms. Based on prior research, patients with symptoms of <16 days duration and no symptoms distal to the knee were considered to have a good prognosis following manipulation. All patients underwent up to two sessions of spinal manipulation treatment and a range of motion exercise. Oswestry disability scores were recorded before and after treatment. If ≥ 50% improvement on the Oswestry was achieved, the intervention was considered a success. Sensitivity, specificity, and positive likelihood ratio were calculated for the association of the two criteria with the outcome of the treatment. 141 patients (49% female, mean age = 35.5 (± 11.1) years) participated. Mean pre- and post-treatment Oswestry scores were 41.9 (± 10.9) and 24.1 (± 14.2) respectively. Sixty-three subjects (45%) had successful treatment outcomes. The sensitivity of the two criteria was 0.56 (95% CI: 0.43, 0.67), specificity was 0.92 (95% CI: 0.84, 0.96), and the positive likelihood ratio was 7.2 (95% CI: 3.2, 16.1). The results of this study demonstrate that two factors; symptom duration of less than 16 days, and no symptoms extending distal to the knee, were associated with a good outcome with spinal manipulation.

A prediction rule to identify low-risk patients with heart failure

Abstract: Objectives: To derive a prediction rule using data available in the emergency department (ED) to identify a group of patients hospitalized for the treatment of heart failure who are at low risk of death and serious complications. Methods: The authors analyzed data for all 33,533 patients with a primary hospital discharge diagnosis of heart failure in 1999 who were admitted from EDs in Pennsylvania. Candidate predictors were demographic and medical history variables and the most abnormal examination or diagnostic test values measured in the ED (vital signs only) or on the first day of hospitalization. The authors constructed classification trees to identify a subgroup of patients with an observed rate of death or serious medical complications before discharge < 2%; the tree that identified the subgroup with the lowest rate of this outcome and an inpatient mortality rate < 1% was chosen. Results: Within the entire cohort, 4.5% of patients died and 6.8% survived to hospital discharge after experiencing a serious medical complication. The prediction rule used 21 prognostic factors to classify 17.2% of patients as low risk; 19 (0.3%) died and 59 (1.0%) survived to hospital discharge after experiencing a serious medical complication. Conclusions: This clinical prediction rule identified a group of patients hospitalized from the ED for the treatment of heart failure who were at low risk of adverse inpatient outcomes. Model performance needs to be examined in a cohort of patients with an ED diagnosis of heart failure and treated as outpatients or hospitalized.

Cervical spine fractures in patients 65 years and older: a clinical prediction rule for blunt trauma.

Abstract: PURPOSE: To determine clinical predictors of cervical spine fracture in the elderly and to develop a clinical prediction rule to guide appropriate imaging in high-risk patients. MATERIALS AND METHODS: Institutional review board approval was received with waiver of informed consent. A retrospective case-control study was performed on blunt trauma patients 65 years and older with cervical spine fractures and on randomly selected control subjects without fracture. Potential predictors of fracture were evaluated through simple and multivariate logistic regression. Simple predictors were grouped into clinically similar composite variables and were analyzed with multivariate logistic regression and recursive partitioning. A clinical prediction rule was generated. The receiver operating characteristic curve was calculated and adjusted through bootstrap validation. Absolute cervical spine fracture probabilities were calculated by using Bayes theorem for all elderly patients and for patients who underwent computed...

Are antibiotics beneficial for patients with sinusitis complaints? A randomized double-blind clinical trial.

Abstract: BACKGROUND Sinusitis is the fifth most common reason for patients to visit primary care physicians, yet clinical outcomes relevant to patients are seldom studied. OBJECTIVE To determine whether patients with purulent rhinitis, "sinusitis-type symptoms," improved with antibiotics. Second, to examine a clinical prediction rule to provide preliminary validation data. METHODS Prospective clinical trial, with double-blinded placebo controlled randomization. The setting was a suburb of Washington, DC, from Oct 1, 2001, to March 31, 2003. All participants were 18 years or older, presenting to a family practice clinic with a complaint of sinusitis and with pus in the nasal cavity, facial pressure, or nasal discharge lasting longer than 7 days. The main outcome measures were resolution of symptoms within a 14-day follow-up period and the time to improvement (days). RESULTS After exclusion criteria, 135 patients were randomized to either placebo (n=68) or amoxicillin (n=67) for 10 days. Intention-to-treat analyses showed that 32 (48%) of the amoxicillin group vs 25 (37%) of the placebo group (P=.26) showed complete improvement by the end of the 2-week follow-up period (relative risk=1.3; 95% confidence interval [CI], 0.87-1.94]). Although the rates of improvement were not statistically significantly different at the end of 2 weeks, the amoxicillin group improved significantly earlier, in the course of treatment, a median of 8 vs 12 days, than did the placebo group (P=.039). CONCLUSION For most patients with sinusitis-type complaints, no improvement was seen with anti-biotics over placebo. For those who did improve, data suggested there is a subgroup of patients who may benefit from antibiotics.

Prospective Validation of a Prediction Model for Isolating Inpatients With Suspected Pulmonary Tuberculosis

Abstract: Background Current guidelines for the control of nosocomial transmission of tuberculosis (TB) recommend respiratory isolation for all patients with suspected TB Application of these guidelines has resulted in many patients without TB being isolated on admission to the hospital, significantly increasing hospital costs This study was conducted to prospectively validate a clinical decision rule to predict the need for respiratory isolation in inpatients with suspected TB Methods A cohort of 516 individuals, who presented to 2 New York City hospitals between January 16, 2001, and September 29, 2002, and who were isolated on admission for clinically suspected TB, were enrolled in the study Face-to-face interviews were conducted to determine the presence of clinical variables associated with TB in the prediction model, including TB risk factors, clinical symptoms, and findings from physical examination and chest radiography Results Of the 516 patients, 19 were found to have TB (prevalence, 37%; 95% confidence interval [CI], 22%-57%) The prediction rule had a sensitivity of 95% (95% CI, 74%-100%) and a specificity of 35% (95% CI, 31%-40%) Using a prevalence of TB of 37%, the positive predictive value was 96% and the negative predictive value was 997% Conclusions Among inpatients with suspected active pulmonary TB who are isolated on admission to the hospital, a prediction rule based on clinical and chest radiographic findings accurately identified patients at low risk for TB Approximately one third of the unnecessary episodes of respiratory isolation could have been avoided had the prediction rule been applied Future studies should assess the feasibility of implementing the rule in clinical practice

Predicting pressure ulcers: cases missed using a new clinical prediction rule.

Abstract: Aim. The aim of this paper is to report a study describing patients with pressure ulcers that were incorrectly classified as ‘not at risk’ by the prediction rule and comparing them with patients who were correctly classified as ‘not at risk’. Background. Patients admitted to hospital are at risk of developing pressure ulcers. Although the majority of pressure ulcers can be predicted using a recently developed prediction rule, up to 30% of patients with pressure ulcers may still be misclassified. Methods. Between January 1999 and June 2000 a prospective cohort study was conducted in two large hospitals in the Netherlands. Patients admitted to neurology, internal, surgical, and elder care wards for more than 5 days were included (n ¼ 1229), and were examined weekly. Information on potential prognostic determinants for pressure ulcers mentioned in the literature was recorded. Outcome was defined as occurrence of a pressure ulcer grade 2 or worse during hospital admission. Results. Patients who developed pressure ulcers experienced more problems with ‘friction and shear’ and underwent surgery more often and longer. Also, they were more often admitted because of malignant conditions. Conclusion. We found no specific characteristics that clearly distinguished patients with pressure ulcers that were incorrectly classified as ‘not at risk’ by the prediction rule frompatientswhowere correctly classified as ‘not at risk’. It appears difficult to improve further on the prediction of pressure ulcers using available clinical information.

A clinical decision rule for management of streptococcal pharyngitis in low-resource settings.

Abstract: Background: Most of the world's children live in regions where laboratory facilities are not available. In these regions, clinical prediction rules can be useful to guide clinicians' decisions on antibiotic therapy for streptococcal pharyngitis, and to reduce routine presumptive antibiotic therapy for all pharyngitis. Methods: Prospective cohort study to assess diagnostic signs and develop a prediction rule. Bivariate and multivariate analyses were used to develop clinical rules. Participants were 410 children in Cairo, Egypt, aged from 2 to 12 y, presenting with complaint of sore throat and whose parents provided consent. Main outcome measures included presence of signs and symptoms, and positive group A beta hemolytic streptococcal (GABHS) culture. Results: 101 (24.6%) children had positive GABHS culture. Pharyngeal exudate, tender or enlarged anterior cervical lymph nodes, season, absence of rash, or cough or rhinitis were associated with positive culture in bivariate and multivariate analyses. Three variables (enlarged nodes, no rash, no rhinitis), when used in a cumulative score, showed 92% sensitivity and 38% specificity in these children. Conclusions: The proposed three-variable clinical prediction rule for GABHS may be useful when diagnostic laboratories are not available. In this setting, the rule identified more than 90% of true cases. Compared to universal treatment of all pharyngitis, the rule will reduce antibiotic use in GABHS-negative cases by about 40%.

A clinical prediction rule for the severe acute respiratory syndrome.

Abstract: TO THE EDITOR: We read with great interest the article by Leung and colleagues (1) on their clinical prediction rule for emergency department diagnosis of the severe acute respiratory syndrome (SARS). During the early period of the 2003 SARS epidemics in Taiwan, we prospectively developed a clinical decision rule from a cohort of febrile patients (2, 3), consisting of a 4-item symptom score and a 6-item clinical score (2). The prediction rule was adopted in our institution and became part of an integrated decision-making process for sorting incoming febrile patients during the epidemic. When validated by a second cohort, our rule showed a sensitivity of 90.2%, a specificity of 80.1%, and an area under the receiver-operating characteristic curve of 0.89 (3). We applied Leung and colleagues' rule to our cohort of 299 febrile patients, including 79 with laboratory-confirmed SARS and 220 without SARS. The sensitivity, specificity, positive predictive value, and negative predictive value were 98.8%, 52.0%, 43.6%, and 99.1%, respectively. The authors should be congratulated for a well-conducted study. However, some aspects of their prediction rule warrant further elaboration. First, the study cohort had a higher proportion of nonfebrile patients with SARS than has been reported elsewhere (4, 5). Because of the study's retrospective design, it is possible that some of these patients might not have had SARS to begin with but were instead cross-infected in hospital settings. This might introduce some misclassification bias and threaten the study's validity. Second, the clinical utility of the rule, if applied as suggested, may be limited in a large outbreak. More than 80% of patients still need hospitalization after triage by the rule. Housing patients with a 21% risk for SARS, quartile 1 in the high-risk group, in a communal isolation ward can be a dangerous practice. Triage of SARS during epidemics depends on the prevalence of the disease in the community and on local policies. Three pieces of informationcontact history, fever, and pulmonary infiltrateneed to be considered. Patients with contact history and pulmonary infiltrates should be admitted regardless of body temperature. Afebrile patients without pulmonary infiltrates could be discharged home and receive daily follow-up of body temperature. Clinical decision rules are not needed for these patients. Febrile patients without pulmonary infiltrates are the most challenging for emergency department staff and should be the focus of a prediction rule. Whether to admit patients with pulmonary infiltrates but no contact history, however, is a policy issue. Well-thought-out clinical prediction rules, along with sound policies, would help communities tackle future SARS epidemics or similar outbreaks.

Reflection and Reaction

Abstract: ative sepsis. The specific issue of P aeruginosa infections remains clinically uncertain. The data are too sparse, the confidence intervals surrounding the results presented here are wide, data regarding empirical treatment are limited to a single study, 6 and controlled comparisons are lacking. We agree with the authors’ conclusion that a large randomised trial may be warranted. The design of such a trial is complex. The optimal comparison would be between appropriate beta-lactam monotherapy and appropriate combination therapy, administered from the onset of antibiotic treatment. A clinical prediction rule may help select patients at high risk for P aeruginosa infections. 15 Allcause, rather than infection-related, mortality should be assessed to answer the question Safdar and colleagues raise: “does combination antimicrobial therapy reduce mortality”?

A clinical prediction rule predicted outcome in patients with low back pain having spinal manipulation and exercise treatment

Abstract: Patients: 131 patients who were 18–60 years of age (mean age 34 y, 58% men), had a primary symptom of LBP, were referred to physical therapy, and had an Oswestry Disability Questionnaire (ODQ) score >30%. Exclusion criteria: serious spinal condition, nerve root compression, pregnancy, or previous surgery to the lumbosacral spine or pelvis. Patients were allocated to receive spinal manipulation plus exercise (n = 70) or exercise alone (n = 61) given by a physical therapist for 4 weeks.

Clinical rule predicts patients likely to benefit from spinal manipulation

Abstract: Question Is it possible to identify the low back pain patients who will respond to spinal manipulation? Design Randomised controlled trial with pre-planned subgroup nalysis. Setting Eight physical therapy clinics in USA. Patients Patients aged 18–60, with a primary complaint of low back pain and an Oswestry Disability score of at least 30%. Exclusions were serious spinal pathology, nerve root compromise, pregnancy, and previous surgery. 543 patients were screened; 131 were eligible and were randomised using sealed envelopes to a manipulation group (70 patients) or an exercise group (61 patients). Interventions Patients in both groups attended physiotherapy for 5 sessions over 3 weeks. The manipulation group received a high velocity thrust spinal manipulation during the first two sessions and then low stress aerobic and lumbar strengthening exercises. The exercise group received exercise alone. Two participants in the manipulation group and 9 in the exercise group discontinued treatment. An independent examiner assessed the patients and classified them as positive on the clinical prediction rule if they met 4 of the 5 following criteria: symptom duration 35 degrees of internal rotation. Outcomes The primary outcome was disability measured using the 0–100% Oswestry disability index, measured at baseline, 1 week, 4 weeks, and 6 months. Treatment success was defined as 50% reduction in disability. All participants completed the baseline assessment and 1 week follow-up, 130/131 the 4 week follow-up, and 92/131 the 6 month follow-up. Analysis was by intention to treat with pre-planned subgroup analysis. Results 47/131 participants were positive to the rule. ANOVArevealed that the outcome depended upon the both the participant's treatment group and status on the rule. Pairwise disability mean (95%CI) differences at one week were: manipulation vs exercise 9.2 (4.4 to 14.1), manipulation (+ve on rule) vs manipulation (-ve on rule) 15.0 (8.5 to 21.5), manipulation (+ve on rule) vs exercise (+ve on rule) 20.4 (13.0 to 28.8) and exercise (+ve on rule) vs exercise (-ve on rule) -1.9 (-8.6 to 4.9). (+ve values signify greater improvement with the first named group in a pair). At 1 week 44% of the manipulation group had a successful outcome, however the success rate was 92% in the manipulation subgroup positive to the rule and only 7% in the subgroup who met less than 3 of the criteria. Conclusion Patients were more likely to benefit from spinal manipulation if they met the clinical prediction rule.