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At least 883 records · Page 49Linked to original sources
PubMed1995

Cognitive behavioral treatment of fibromyalgia syndrome: a followup assessment.

OBJECTIVE: In a previous study, we showed that cognitive behavioral therapy (CBT) was effective in the short term treatment of fibromyalgia (FMS). We tested the hypothesis that a pooled index of 10 target psychometric outcomes would show overall improved outcome at longterm followup versus pretreatment. METHODS: Using a quasiexperimental design and validated psychometric instruments, we compared pretreatment psychometric variables with longterm outcomes in the 25 subjects who had completed the earlier study. A distinction was made between target variables the program had specifically addressed and nontarget variables not specifically addressed. RESULTS: Twenty-two subjects participated at a mean of 30 months after discharge from the program. As at short term followup, no nontarget variable changed from pretreatment to longterm assessment. The short term improvement that had been observed in all 10 target variables was maintained in 3 variables at a Bonferroni corrected alpha level of 0.005: worry, p < 0.001; observed pain behavior, p < 0.001; and control over pain, p < 0.002. All 10 target variables changed in the direction of improvement. A pooled index of these 10 variables showed statistically significant improvement from baseline (p < 0.002). CONCLUSION: Our results suggest that CBT may have a role in the longterm treatment of FMS.

Adult↗
PubMed1994

Relation between body temperature and dexmedetomidine-induced minimum alveolar concentration and respiratory changes in isoflurane-anesthetized miniature swine.

Dexmedetomidine (DEX), an alpha 2-receptor agonist, is the pharmacologically active d-isomer of medetomidine, a compound used as a sedative in veterinary medicine. Isoflurane anesthetic requirement (minimum alveolar concentration; MAC), rectal temperature, and cardiorespiratory variables were studied in chronically instrumented Yucatan miniature swine during DEX (20 micrograms/kg of body weight)-induced changes in body temperature. All studies were performed at room temperature of 22 C. The DEX was given as a 2-minute infusion into the left atrium. Each pig was studied twice. For protocol 1, the core temperature of the pigs was maintained at (mean +/- SD) 38.2 +/- 0.5 C by use of a thermostatically controlled water blanket and a heating lamp. For protocol 2, the core temperature was not externally manipulated and it decreased from 38.2 +/- 0.4 C to 32.2 +/- 1.2 C during the more than 3 hours of the protocol. Control isoflurane MAC was 1.66 +/- 0.2% and was 1.74 +/- 0.3% for protocols 1 and 2, respectively; DEX decreased MAC by 34 and 44%, respectively. For protocol 1, reduction in MAC after DEX administration returned by 50 and 80% at 84 and 138 minutes, respectively. If rectal temperature was not maintained (eg, allowed to decrease), MAC was reduced by 57% at the same time as the return to 80% in the swine with maintained body temperature. Respiratory rate and minute ventilation were significantly higher in swine with maintained temperature. The PaCO2 was lower and, accordingly, pH was higher in these swine. Blood pressure and heart rate were not affected by temperature changes.

Adrenergic alpha-Agonists↗
PubMed1994

Electrosurgical injuries during laparoscopy: prevention and management.

Despite the fact that electrophysics and its application to surgery, in particular endoscopic surgery, is a discreet science, there is little attention paid to the applied principles of the physics involved when surgeons receive their formal training in the technical aspects of surgery. Most training programs consider the discipline of electrosurgery as a skill that is left to the 'hands on' exposure of the student, and that the skills and knowledge of the average professor have been awarded through a 'grandfather' process of credentials. As a result, many myths have been perpetuated over the past decades since William Bovie introduced the first electrosurgical diathermy machine using high frequency radio waves instead of heated instruments (cautery) to destroy human tissue. Electrogenerators, today, have become finely tuned instruments that offer many versatile variables for the contemporary surgeon to harness and deliver, in either a discreet or broad manner, to tissue to obtain a desired effect and outcome.

Electric Injuries↗
PubMed1994

[Hygienic aspects of the microclimate in intensive management of rabbits].

In a four-row cowshed adapted for rabbit housing, air temperatures and humidity were recorded ambulantly and instrumentally, air flow rate, cooling variable, gas content in the air, microbial contamination of air and dust deposition were determined ambulantly in the years 1991-1992 and in January to April 1993. The values of ambulant measurings show that at the outside temperature -0.5 degrees C to -5.0 degrees C the microclimate quality decreases particularly with respect to the drop of air temperature in the cowshed below 10.0 degrees C, to the increase in cooling variable up to the value 53.17 mW/cm2 and to the increase in NH3 and CO2 content to 50 ppm and/or 0.45 vol.% in absolute maximum values. In these circumstances, the average determined values of both gases are higher than the standard prescription. At outside temperatures above 27.0 degrees C the average relative air humidity in the cowshed made 69.20% for the average temperature of 25.0 degrees C. To avoid the water vapor tension exceeding the limit in the cowshed air above the value 14.1 mm Hg, when sultry atmosphere sets in, the average relative air humidity should be maximally 59.0%. Hence the cowshed was found to be insufficiently ventilated at high outside temperatures above 27.0 degrees C, and it is recommended to increase the ventilator performance and at the same time to reduce water evaporation from catchpit surfaces when urine output of rabbits is excessive as a result of the increased water intake. Temperature and air humidity readings confirmed the need of heating source installation when the outside temperatures drop below 0.0 degrees C. Evaluation of air microbial contamination showed high counts of molds and particularly of micrococci in comparison with the ambience of a cage facility for piglet raising at a repopulation station with strict hygienic regime. Microbial picture of dust deposition was positively influenced by longitudinal aerosol disinfection of the air in the cowshed.

Air Microbiology↗
PubMedDate not supplied

Guidance for using a pilot study: an example of research on minority children.

Sound research requires careful definition of the research problem, identification of critical variables and the sources of data for variables, design of procedures and instruments to ensure valid and reliable data, and appropriate and comprehensive data analyses. Additionally, adequate personnel, time, and budgetary resources are required. To help ensure that research addressing minority health issues meets these requirements, this article provides investigators with practical guidance for using pilot projects, not simply as small nongeneralizable studies but also as techniques to address each of these issues. The authors provide examples from real-life research, addressing the health outcomes of minority children who receive care through the Early and Periodic Screening Diagnosis.

Child↗
PubMed1994

Short-term longitudinal study of maternal ratings of temperament in samples of children with Down syndrome and children who are developing normally.

Ratings of temperament for 32 children with Down syndrome and 44 children who were developing normally over the developmental range from 12 to 36 months were compared. Mothers completed the Toddler Temperament Scales and/or the Bates Infant/Child Characteristics Questionnaire at two time points. Analyses tested for diagnostic group differences in temperament ratings. Multivariate repeated measures analyses of variance, with diagnosis and developmental age as grouping variables, were run for both instruments. For the Toddler Temperament Scales, no between-subjects main effects of diagnosis or interactions were significant; however, a significant multivariate main effect for diagnosis was obtained for the Bates Scales. Ordering consistency for the two samples was considered separately. Cross-time correlations were generally significant; however, relations tended to be of greater magnitude in the normally developing group. Results suggest that the development of temperament, as assessed with maternal ratings, follows a common path in these two groups.

Child, Preschool↗
PubMedDate not supplied

[Midwives' perception of reproductive risk factors].

Midwives in rural areas of the State of Morelos are one of the most important resources used by rural women for health care of pregnancy, delivery and the puerperium. This work was aimed at identifying midwives perceptions of pregnant women's risk factors, in order to include this knowledge in reproductive health programs which articulate institutional and traditional health systems. We applied a questionnaire to all midwives in the Municipalities of Ocuituco, yecapixtla and Zacualpan, Morelos (n = 35). Four key informants were selected and interviewed. These instruments enabled us to measure variability in perception of risk factors. Knowledge of risk factors is defective among midwives. Previous training made a big difference. Sixty three per cent of midwives who attended training courses are better qualified from an academic medicine point of view. Only 28.7 per cent of non-trained midwives (43% for both groups), indicating that sociocultural aspects prevail over technical training in midwives perceptions of reproductive risk factors.

Adult↗
PubMedDate not supplied

Monitoring in the operating room: current techniques and future requirements.

Review of a recent lawsuit and study of operating room cardiac arrests reveal that ventilatory problems are a major source of intraoperative morbidity and mortality. Tidal volume and airway gas composition are critical to the anesthesiologist who must determine the depth of an inhalation anesthetic. Yet, current instrumentation does not permit these variables to be measured conveniently. In this paper, current techniques for monitoring cardiovascular physiology are review, and considerable attention is focused on the problem of and the requirements for ventilatory monitoring in the operating room. The high dollar cost of infrequent untoward events is discussed, as well as the additional problem this creates because individual anesthesiologists may receive little positive reinforcement in encouraging the development of more sophisticated monitoring techniques.

Anesthesia↗
PubMed1996

Diurnal and weekly variation of tardive dyskinesia measured by digital image processing.

The diurnal and weekly variability of tardive dyskinesia (TD) was assessed instrumentally by digital image processing. Weekly assessments were obtained in ten patients over a 6-week period. In six of the ten patients, assessments were obtained four times over a single 12-h period. Results indicate that TD movements measured by instrumental assessment vary from week to week and throughout the day. Factors that appear to have affected the variability were changes in medications and the time of day when the assessments were conducted.

Adult↗
PubMed1993

Gender differentiated receptivity to sexuality education curricula by adolescents.

Teenagers comprise a substantial proportion of the 'at risk' population for sexually transmissible diseases (STDs) and AIDS. They are, also, potentially amenable to the curriculum influences of the high school, suggesting that a high profile needs to be accorded to sexuality education curricula. The variable of receptivity along gender lines to sexuality education programs is explored and reported in this study. An instrument was constructed to measure key constitutive variables in the dimensions of meaning and attitude, and administered to a sample of Western Australian high school students (N = 533). Data were subjected to a two-way ANOVA with sex and school as the dependent variables. It was found that there are differences in receptivity to sexuality education curricula between male and female high school students; that receptivity, irrespective of gender, rises with increasing curriculum provision and with males showing higher gains when compared with females. The findings have implications for policy makers and administrators in providing access to extensive school-based sexuality education curricula.

Adolescent↗
PubMed1997

Temporomandibular disorders: Part II. A comparison of psychologic profiles in Australian and Finnish patients.

Recent recommendations regard musculoskeletal disorders of the masticatory system as dual-axis disorders, but little comparative data of psychologic factors across different pain populations are available. In this study, presenting psychologic profiles were assessed in 40 Australian and 42 Finnish patients diagnosed with temporomandibular disorders. Findings were compared with those of a group of Australian patients reporting acute dental pain and with reference to response to conservative management. The psychologic testing instrument incorporated cognitive, motivational/affective, and illness behavior variables, and it was based on validated general pain questionnaires (Coping Strategies Questionnaire and Illness Behavior Questionnaire). This instrument was found internally reliable in the majority of its subscales in the group studies and provided comparable data to other pain populations. Significant differences in the presenting psychologic profiles were found according to nationality, type of pain suffered, and treatment outcome. Affective disturbance, hypochondriasis, lack of cognitive control, and feeling ill with symptoms were identified in discriminant function analysis as potential predictors of treatment outcome, and they correctly classified 79% of the Australian and 87% of the Finnish patients with temporomandibular disorders. It was concluded that psychologic profiles differed in the two nationalities and were related to treatment outcome. The concept of multiaxial assessment was supported.

Activities of Daily Living↗
PubMedDate not supplied

Surveillance and screening of American cutaneous leishmaniasis by Colombian primary health care workers using a clinical prediction rule.

Confirmed cases of American cutaneous leishmaniasis (ACL) and other dermatological diseases were evaluated in Colombia with a clinical prediction rule independently by 3 types of evaluators: community health volunteer (CHV), practical nurse (PN) and programme physician (PP). The adapted prediction rule included 6 variables based upon clinical-historical information. The screening instrument was a rotating tower of coloured squares, one colour for each variable. A score ranging from 0 to 7, and a cutoff point of > or = 4 was selected for ACL classification (sensitivity 94.3%, specificity 53.3% and efficiency 80.3%). Disease classification, total score, and variable-specific score obtained by CHVs and PNs were compared to those obtained by a PP. The impact on case detection in the study area was assessed. Both types of primary health worker had a high agreement with the PP (sensitivity) on the classification of patients with ACL by score, CHV (92.3%) and PN (93.3%). Case detection of ACL increased 3-fold over that observed one year earlier. This screening instrument and prediction rule, when incorporated into a community surveillance programme for ACL, can facilitate greater case detection and appropriate referral for more-specific diagnostic procedures.

Colombia↗
PubMed2006

Current concepts in validity and reliability for psychometric instruments: theory and application.

Validity and reliability relate to the interpretation of scores from psychometric instruments (eg, symptom scales, questionnaires, education tests, and observer ratings) used in clinical practice, research, education, and administration. Emerging paradigms replace prior distinctions of face, content, and criterion validity with the unitary concept "construct validity," the degree to which a score can be interpreted as representing the intended underlying construct. Evidence to support the validity argument is collected from 5 sources: CONTENT: Do instrument items completely represent the construct? RESPONSE PROCESS: The relationship between the intended construct and the thought processes of subjects or observers. INTERNAL STRUCTURE: Acceptable reliability and factor structure. RELATIONS TO OTHER VARIABLES: Correlation with scores from another instrument assessing the same construct. CONSEQUENCES: Do scores really make a difference? Evidence should be sought from a variety of sources to support a given interpretation. Reliable scores are necessary, but not sufficient, for valid interpretation. Increased attention to the systematic collection of validity evidence for scores from psychometric instruments will improve assessments in research, patient care, and education.

Humans↗
PubMed1998

Assessment of the influence of citrate concentration on the International Normalized Ratio (INR) determined with twelve reagent-instrument combinations.

Citrate concentration is one of the variables that can affect coagulation tests. However, few studies have so far been performed to assess the magnitude of this effect on coagulation tests in general and PT in particular. The aim of this study was to assess the extent of influence of citrate concentration on the PT test with results expressed as INR. Twelve reagent-instrument combinations (systems) were calibrated vs. the Reference Preparation BCT/441 using plasmas collected in either 105 mM or 129 mM citrate from normals and anticoagulated patients (OAT). PTs for plasmas collected in 129 mM citrate were longer than those collected in 105 mM both for normals and patients on OAT, but the ratios (patient-to-normal clotting times) for the two citrate concentrations were significantly different in many instances, implying that the International Sensitivity Index (ISI) is also different. ISIs for calibrations with plasmas collected in 105 mM were greater (up to 10%) than those with plasmas collected in 129 mM citrate. When PT ratios were transformed into INR using crossover ISIs (i.e., plasmas collected in 105 mM and ISI determined with plasmas collected in 129 mM citrate, or vice versa) we found that an INR of 4.5 could be up to 20% apart from the value that would have been obtained if the appropriate ISI was used. Moreover, if the ISI determined with the manual technique was used to convert PTs obtained with a particular instrument into INR, the effect of citrate concentration was even greater (INR difference up to 64%). Should these observations be valid for other systems, they might provide additional explanations for the frequent reports which document discrepancies in the INR determined with different systems to which incorrect ISI might have been applied. World-wide consensus on a single citrate concentration to collect patients' as well as lyophilized plasmas to be used in External Quality Assessment Schemes and for local system calibration is therefore urgently needed.

Blood Coagulation Tests↗
PubMed2006

Objectives for correction and related instrumentation strategies in scoliosis surgery for Lenke curve types 2, 3 and 5.

A recent study revealed a large variability among a group of 32 spine surgeons in the pre-operative instrumentation planning for the same 5 AIS patients. It is hypothesized that this variability may be attributed to different objectives for correction. In this new study we analyzed the objectives of correction and the related instrumentation strategies for three different Lenke curve types. Nine experienced surgeons from the Spinal Deformity Study Group were surveyed and asked to assess 11 different geometric parameters describing the spinal deformities for three different Lenke curve types (2, 3 and 5) according to their importance for an optimal 3D correction. These same 9 surgeons were asked to provide their preferred posterior instrumentation planning for three patients with the same curve types. Statistical analyses included: median, interquartile range IQR and Wilcoxon non parametric test. There was an overall agreement that sagittal and coronal balances were the most important parameters for an optimal correction. All other parameters were highly variable depending on the curve-type. Mobility was more important for the Lenke curve types 3 and 5 than for type 2 (p<0.032). A comparative analysis based on the coronal curves (Cobb) and the number of unfused vertebrae revealed a significant difference (p<0.025) between the correction objectives of the surgeons and their posterior instrumentation planning. In the three curves types analyzed, there is a large variability in scoliosis correction objectives, which is surgeon and curve-type dependent. There is a disagreement between the correction objectives and the instrumentation strategies. Optimal configuration of surgical instrumentation remains a controversial topic.

Adolescent↗
PubMed1993

Clinical use of the erythrocyte sedimentation rate in the evaluation of febrile intravenous drug users.

STUDY OBJECTIVE: To investigate the use of the erythrocyte sedimentation rate in the evaluation of febrile IV drug users. DESIGN: Prospective observational cohort study. SETTING: Municipal hospital emergency department. TYPE OF PARTICIPANTS: One hundred six IV drug users aged 18 years or older, with rectal temperatures of 37.8 C or more. INTERVENTIONS: Clinical and laboratory variables were obtained by trained research assistants, using a standardized data collection instrument. RESULTS: The erythrocyte sedimentation rate was the only variable consistently associated with illness severity in both the univariate and multivariable analyses (P < .0001). At an erythrocyte sedimentation rate of 100 mm/hr or more, the test had a specificity of 96% (95% confidence interval, 81% to 100%). In contrast, the erythrocyte sedimentation rate displayed a relatively poor sensitivity at low values (88% [95% confidence interval, 77% to 95%] at an erythrocyte sedimentation rate less than 20). CONCLUSION: An erythrocyte sedimentation rate of 100 or more should be regarded as a marker for serious illness in IV drug users with fever, but a "normal" erythrocyte sedimentation rate of less than 20 does not reliably exclude the presence of serious disease in this patient population.

Adult↗
PubMed1997

Perception of flight information from EFIS displays.

A pilot's perception of variables presented on the Electronic Flight Instrument System, EFIS, was investigated. A stimulus response technique was used to determine the accuracy and speed of the perception process. By varying the exposure time of the stimuli, it is shown that the perception of a variable's magnitude is faster and more accurate than the perception of the first derivative or rate of that variable. Results of experiments on roll and pitch attitude perception, the influence of scale division, and the perception of the indicated airspeed, are shown.

Aerospace Medicine↗
PubMed1997

Equating the MOS SF36 and the LSU HSI Physical Functioning Scales.

This study equates the physical functioning subscales of the Medical Outcomes Study Short Form 36 (SF36) and the Louisiana State University Health Status Instruments (LSU HSI). Data from the SF36's 10-item physical functioning scale, the PF10, and the LSU HSI's 29-item Physical Functioning Scale (PFS), were fit to separate and mixed Rasch rating scale models. Data were provided by a convenience sample of 285 patients waiting for appointments in a public hospital general medicine clinic. Difficulty estimates for a subset of similar items from the two instruments were highly correlated (.95), indicating that the items from the two scales are working together to measure the same variable. The measures from the two equated instruments correlate .80 (.86 when disattenuated for error). Of the two instruments, the PFS's error is lower, model fit is better, and reliability coefficients are higher. Both instruments measure physical functioning, and can do so in a common unit of measurement. Conversion tables are provided for transforming raw scores from either instrument into the common metric.

Adult↗