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PubMedDate not supplied

[Performance of nursing students in the intramuscular administration of drugs].

The goal of the present study was to compare the performance of two groups of nursing undergraduate students, submitted to two different teaching methods, in their ability to perform the intramuscular injection on clients needing the procedure. Both, control (CG) and experimental group (EG) (n = 35 each) were submitted to traditional method and instructional method respectively, according to the methodological procedure described by Nogueira (1995). The performance of the students was evaluated by a nurse who had no knowledge of the group each student belong. The nurse used the "check-list" in order to evaluate the performance of student. The results indicate that the time spent by the students of each group was approximately the same i.e. 9.4 min for CG and 9.3 for EG. The students of the control group showed ordinary performance (42.9%), good performance (48.9%) and very good performance (8.5%) whereas those of the EG showed ordinary performance (5.7%), good performance (60%) and very good performance (34.3%). The present results shows that the students are responsible by their own learning, motivating us to use new teaching methods on nursing undergraduate course.

Adolescent↗

PubMed1999

Effect of number of home exercises on compliance and performance in adults over 65 years of age.

BACKGROUND AND PURPOSE: There is limited research on the effects of the number of exercises a person is told to perform on compliance and performance, as defined by cueing requirements, correct alignment, and quality of movement. Some studies of medication suggest that compliance decreases as the number of medications increases. The purpose of this study was to determine whether older adults comply and perform better (ie, requiring less cueing, exhibiting correct alignment, and exhibiting controlled, coordinated, and continuous movements) when they are asked to do 2, 5, or 8 exercises. SUBJECTS: Subjects were 11 women and 4 men, aged 67 to 82 years (X=72.8), who were living independently in their communities. METHODS: Subjects were randomly prescribed 2, 5, or 8 general strengthening home exercises. They were instructed on their exercises at an initial session and asked to record the number of repetitions performed each day in a self-report exercise log. At a return session 7 to 10 days later, subjects were scored on their performance of the prescribed exercises using a newly designed assessment tool. RESULTS: The group that was prescribed 2 exercises performed better, as defined by their performance tool score, than the group that was prescribed 8 exercises. The group that was prescribed 5 exercises was not different from the groups that performed 2 or 8 exercises. No differences were found among groups regarding the self-report measurement of compliance. There was a moderate correlation between performance scores and the self-report percentage rates. CONCLUSION AND DISCUSSION: Subjects who were prescribed 2 exercises performed better than subjects who were prescribed 8 exercises. The question of an optimal number of exercises to prescribe to elderly people warrants further study.

Aged↗

PubMed1999

An examination of mood changes and performance in a professional basketball team.

BACKGROUND: The purpose of this study was to examine the relationship between the Profile of Mood States (POMS) and performance in a professional basketball team. METHODS PARTICIPANTS: seven male professional basketball players playing for the defending champions of the Israel Basketball League participated in this study. EXPERIMENTAL DESIGN: the POMS was administered seven times (T1-T7) during the season. The initial POMS administration was performed three weeks following the start of preseason practice and one day prior to the first basketball game. Each of the other POMS administrations were performed two days following a game and no more than 2 days before the next game. RESULTS: Typical iceberg profiles were observed during T1, T2 and T3, which coincided with successful performance (winning percentages greater than 60% between each POMS administration). Subsequent decreases in performance between T3 and T4 (a 33% winning percentage) resulted in a decrease in vigor and an increase in anger. As team performance improved between T4 and T5 (winning percentage again above 60%), vigor returned to its original level. However, the mood states anger and depression remained elevated, even during successful team play. This may have been related to problems independent of basketball performance (coaching and financial). CONCLUSIONS: These results suggest that the mood state vigor may be reflective of team performance. In addition, mood states appear to be influenced more by performance or experience, rather than performance being influenced by changes in mood states.

Adult↗

PubMed1979

Performance and acquisition of serial position sequences by pigeons as measures of behavioral toxicity.

A procedure has been developed to measure the repeated acquisition of serial position sequences and to study the effects of drugs and toxic chemicals on the behavior generated by the procedure. Thus far experiments using the procedure have shown: (1) Performance schedules generate lower error rates than corresponding acquisition schedules: (2) Addition of a reset contingency further decreases errors under both performance and acquisition schedules: (3) Chained acquisition and performance schedules generate lower error rates than corresponding tandem acquisition and performance schedules: (4) Chained acquisition and performance schedules produce behavior that usually is more sensitive to drugs than corresponding tandem acquisition and performance schedules: (5) Acquisition schedules produce behavior that usually is more sensitive to drugs than corresponding performance schedules: and (6) Lead is an exception in that it produced clearer effects under a chained performance schedule with a reset contingency than under a corresponding acquisition schedule. The greater sensitivity to drug effects of behavior under acquisition schedules than behavior under performance schedules and of behavior under chained schedules may be a function of the baseline error rates, rather than the behavioral processes of acquisition, performance, and stimulus control.

Animals↗

PubMed1996

Instrument flying performance after G-induced loss of consciousness.

INTRODUCTION: While both the USAF and the USN have characterized the immediate sequelae of G-induced loss of consciousness (G-LOC) as resulting in approximately 24 s of incapacitation, very little is known about the effect of a G-LOC immediately after this incapacitation period. This study is an attempt to determine the effect of G-LOC on instrument flying performance immediately after G-LOC. METHOD: In order to establish their flying performance baselines, 29 Canadian Forces (CF) pilots attending the high sustained G (HSG) course flew 3 iterations of a 15-min instrument flying task on the day prior to their HSG course. All 29 pilots performed this same task the next day within 5 min of completing the centrifuge training. In addition, the pilots who experienced G-LOC flew the task again 45 min after G-LOC. Flying performance was assessed by calculating Root Mean Square (RMS) error on 11 flight parameters. These RMS values were submitted to a multivariate analysis of variance. RESULTS: Of the 29 pilots, 12 experienced G-LOC during the centrifuge training. The flying performance of the 17 non-G-LOC pilots was not affected by their exposure to HSG. Of the 12 G-LOC pilots, 11 had no measurable performance decrement while 1 pilot, after a severe G-LOC, stalled and "spun-in" on take-off and then (after being re-established on the outbound radial) could not complete the task. This same pilot flew the task very well 45 min later. This study did not identify a degradation in flying performance after HSG nor after G-LOC except in the 1 pilot. CONCLUSIONS: Whether or not a pilot's flying performance is affected after G-LOC may be related to the severity of the G-LOC. Some pilots may experience seizure activity relating to the G-LOC with a resulting sustained performance decrement that appears to resolve by 45 min. It is possible that some of the other G-LOC pilots in the study might have had measurable performance decrements if we had been able to have them fly the task while they were still in the gondola (i.e., immediately after the G-LOC).

Adult↗

PubMed1998

Female exposure to high G: performance of simulated flight after 24 hours of sleep deprivation.

BACKGROUND: Ground-based research has investigated the loss of cognitive function in the extreme conditions of G-induced loss of consciousness, however, little is known about pilots' abilities to maintain cognitive performance throughout prolonged conscious exposure in the high-G environment. The effects of fatigue and G layoff on performance during exposure to high G are mostly unknown for the female population. METHODS: This research was conducted on the centrifuge Dynamic Environment Simulator. Active-duty personnel (8 male and 8 female) were trained to fly the F-16 simulation while 30 performance measures were recorded. Performance was re-evaluated after 24 h of sleep deprivation. RESULTS: Neither male nor female overall performance was affected significantly by sleep status, although individual tasks showed sensitivity; call-sign reaction time was longer by 33%, and missile survival was less likely. Also, when sleep deprived, perceived effort and physical demand were higher while perceived performance was lower. No differences in performance were found in either gender due to lay-off, although some physiologic deconditioning was apparent. Women commanded and endured the same amount of G load as men, however, on average they could not perform the tracking task quite as well. CONCLUSIONS: Sleep deprivation (24 h) produced sensations of fatigue and frustration, but overall performance was not reduced. The ability of personnel to complete a complex defensive maneuver was reduced when they were sleep deprived. The women that we tested apparently could not optimize the tracking task as well as their male counterparts when Gz was in the simulation. None of these results were sufficient to suggest that women should not be allowed to compete for flying assignments in high-performance aircraft.

Aerospace Medicine↗

PubMed2005

Early experience with pay-for-performance: from concept to practice.

CONTEXT: The adoption of pay-for-performance mechanisms for quality improvement is growing rapidly. Although there is intense interest in and optimism about pay-for-performance programs, there is little published research on pay-for-performance in health care. OBJECTIVE: To evaluate the impact of a prototypical physician pay-for-performance program on quality of care. DESIGN, SETTING, AND PARTICIPANTS: We evaluated a natural experiment with pay-for-performance using administrative reports of physician group quality from a large health plan for an intervention group (California physician groups) and a contemporaneous comparison group (Pacific Northwest physician groups). Quality improvement reports were included from October 2001 through April 2004 issued to approximately 300 large physician organizations. MAIN OUTCOME MEASURES: Three process measures of clinical quality: cervical cancer screening, mammography, and hemoglobin A1c testing. RESULTS: Improvements in clinical quality scores were as follows: for cervical cancer screening, 5.3% for California vs 1.7% for Pacific Northwest; for mammography, 1.9% vs 0.2%; and for hemoglobin A1c, 2.1% vs 2.1%. Compared with physician groups in the Pacific Northwest, the California network demonstrated greater quality improvement after the pay-for-performance intervention only in cervical cancer screening (a 3.6% difference in improvement [P = .02]). In total, the plan awarded 3.4 million dollars (27% of the amount set aside) in bonus payments between July 2003 and April 2004, the first year of the program. For all 3 measures, physician groups with baseline performance at or above the performance threshold for receipt of a bonus improved the least but garnered the largest share of the bonus payments. CONCLUSION: Paying clinicians to reach a common, fixed performance target may produce little gain in quality for the money spent and will largely reward those with higher performance at baseline.

Benchmarking↗

PubMed2007

Association between performance measures and clinical outcomes for patients hospitalized with heart failure.

CONTEXT: Assessment of quality of care in heart failure has focused on the development and use of process-based performance measures, with the presumption that these processes are associated with improved clinical outcomes. However, this link remains largely untested. OBJECTIVE: To examine the relationship between current American College of Cardiology/American Heart Association (ACC/AHA) performance measures for patients hospitalized with heart failure and relevant clinical outcomes. DESIGN, SETTING, AND PATIENTS: The Organized Program to Initiate Lifesaving Treatment in Hospitalized Patients With Heart Failure, a registry and performance improvement program for patients hospitalized with heart failure. Sixty- to ninety-day postdischarge follow-up data were prospectively collected from 5791 patients at 91 US hospitals in a prespecified 10% sample between March 2003 and December 2004. Mean patient age was 72.0 years, 51% were male, 78% were white, and 42% had ischemic etiology. Multivariable and propensity-adjusted analyses were performed to assess the process-outcome relationship for each performance measure in eligible patients. Additionally, we evaluated the process-outcome link of a potential performance measure for beta-blockade at discharge among eligible patients hospitalized with heart failure. MAIN OUTCOME MEASURES: Sixty- to ninety-day mortality and combined mortality/rehospitalization rates. RESULTS: Mortality during follow-up was 8.6% and mortality/rehospitalization was 36.2%. None of the 5 ACC/AHA heart failure performance measures was significantly associated with reduced early mortality risk, and only angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use at discharge was associated with 60- to 90-day postdischarge mortality or rehospitalization. Beta-blockade at the time of hospital discharge, currently not a heart failure performance measure, was strongly associated with reduced risk of mortality (hazard ratio, 0.48; 95% confidence interval, 0.30-0.79; P = .004) and mortality/rehospitalization during follow-up. CONCLUSIONS: Current heart failure performance measures, aside from prescription of an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker at discharge, have little relationship to patient mortality and combined mortality/rehospitalization in the first 60 to 90 days after discharge. Additional measures and better methods for identifying and validating heart failure performance measures may be needed to accurately assess and improve care of patients with heart failure.

Adrenergic beta-Antagonists↗

PubMed2007

Performance assessment for radiologists interpreting screening mammography.

When interpreting screening mammograms radiologists decide whether suspicious abnormalities exist that warrant the recall of the patient for further testing. Previous work has found significant differences in interpretation among radiologists; their false-positive and false-negative rates have been shown to vary widely. Performance assessments of individual radiologists have been mandated by the U.S. government, but concern exists about the adequacy of current assessment techniques. We use hierarchical modelling techniques to infer about interpretive performance of individual radiologists in screening mammography. While doing this we account for differences due to patient mix and radiologist attributes (for instance, years of experience or interpretive volume). We model at the mammogram level, and then use these models to assess radiologist performance. Our approach is demonstrated with data from mammography registries and radiologist surveys. For each mammogram, the registries record whether or not the woman was found to have breast cancer within one year of the mammogram; this criterion is used to determine whether the recall decision was correct. We model the false-positive rate and the false-negative rate separately using logistic regression on patient risk factors and radiologist random effects. The radiologist random effects are, in turn, regressed on radiologist attributes such as the number of years in practice. Using these Bayesian hierarchical models we examine several radiologist performance metrics. The first is the difference between the false-positive or false-negative rate of a particular radiologist and that of a hypothetical 'standard' radiologist with the same attributes and the same patient mix. A second metric predicts the performance of each radiologist on hypothetical mammography exams with particular combinations of patient risk factors (which we characterize as 'typical', 'high-risk', or 'low-risk'). The second metric can be used to compare one radiologist to another, while the first metric addresses how the radiologist is performing compared to an appropriate standard. Interval estimates are given for the metrics, thereby addressing uncertainty. The particular novelty in our contribution is to estimate multiple performance rates (sensitivity and specificity). One can even estimate a continuum of performance rates such as a performance curve or ROC curve using our models and we describe how this may be done. In addition to assessing radiologists in the original data set, we also show how to infer about the performance of a new radiologist with new case mix, new outcome data, and new attributes without having to refit the model.

Adult↗

PubMed2000

Performance standards: piece of cake or pie in the sky?

BACKGROUND: Centrally mandated levels of performance are now common in the Veterans Health Administration. Performance standards for ambulatory procedures were developed based on HCFA data. The 11 procedures to be measured were arthroscopy, breast biopsy, eyelid procedures, lens/cataracts, bronchoscopy, endoscopy, colonoscopy, hernia repair, cystoscopy, laparoscopy, and cardiac catheterization. Were the performance standards for ambulatory procedures reasonable and achievable in a tertiary care VA? METHODS: Ambulatory procedure performance standards for the 11 selected procedures were evaluated for Fiscal Year 1998 at one tertiary care VA and at each of the 22 Veteran's Integrated Service Networks (VISNs). Further review was undertaken for those procedures in which performance was below the fully successful level. This included chart reviews at the tertiary care VA and analysis of caseloads by VISN. Descriptive statistics were used as well as Student's t test to analyze the difference in means. RESULTS: The tertiary care VA performed at the fully successful level for 6 procedures and at the exceptional level for 3 procedures. Performance levels for bronchoscopy and laparoscopy were below the preset goals. At the VISN level, 8 VISNs performed at the fully successful/exceptional level for all 11 procedures. The remaining 14 were deficient in 1 to 4 procedures. Eight of the VISNs were deficient in 2 or 3 procedures. Six VISNs were deficient in laparoscopy. CONCLUSIONS: The majority of centrally mandated performance standards appear to be reasonable and achievable. One notable exception is laparoscopy. Surgeons should understand how performance standards are calculated at their institution and review the data carefully for any systematic errors. Underperformance can be used as an opportunity to improve both data collection and outcomes.

Ambulatory Surgical Procedures↗

PubMed2004

Interindividual variation of isolated muscle performance and fibre-type composition in the toad Bufo viridus.

Interindividual analyses of physiological performance represent one of the most powerful tools for identifying functional positive and negative linkages between various performance traits. In this study we investigated functional linkages in the whole-gastrocnemius performance of juvenile Bufo viridis by examining interindividual variation in in vitro muscle performance and muscle fibre-type composition. We used the work-loop technique to investigate the maximum in vitro power output and fatigue resistance of the gastrocnemius muscle during repeated sets of three cycles at the cycle frequency of 5 Hz, simulating an intermittent style of locomotion. We found several significant correlations between different measures of in vitro muscle performance, including a negative correlation between maximum net power output and fatigue resistance of power, indicating functional trade-offs between these performance traits. We also investigated the extent of individual variation in the proportions of different fibre types, and tested for correlations between individual variation in muscle fibre-type composition and the previously measured isolated muscle performance. Fast glycolytic fibres represented 84.0 +/- 3.4% of the muscle, while the combined slow oxidative and fast oxidative-glycolytic fibres represented 16 +/- 3.4%. We found no significant correlations between measures of in vitro muscle performance and the proportion of different fibre types in the gastrocnemius muscle. However, despite this lack of correlation between whole-muscle performance and muscle fibre-type composition data, we suggest the functional linkages detected between different measures of in vitro muscular performance have important ecological and evolutionary consequences.

Animals↗

PubMed2006

The effects of temperature and inter-individual variation on the locomotor performance of juvenile turtles.

The effects of temperature on aquatic and terrestrial locomotor performance, including measures of burst speed, endurance, and righting response, the inter-individual correlation between measures of locomotor performance, and the temporal repeatability of performance were assessed in juvenile western painted turtles, Chrysemys picta bellii. Locomotor performance increased as temperature increased, with Q(10) values ranging from 1.33 to 1.98 for burst speed and 2.28 to 2.76 for endurance measures. Righting response performance also increased with temperature. Aquatic and terrestrial measures of locomotor performance were highly correlated; however, righting response was not correlated with any other measure of performance. Measures of terrestrial locomotor performance were highly repeatable over the entire 30-week study period, whereas aquatic locomotor performance was only repeatable through week 12. The righting response was repeatable over a 6-week study period. Both the interindividual variation and temperature effects on locomotor performance likely influences the survival of turtles, especially juveniles, by affecting the length of time turtles are exposed to potential predators and their ability to escape.

Animals↗

PubMed1988

Nicotine enhances delayed matching-to-sample performance by primates.

The non-human primate provides an excellent model for studies of learning and memory, and one particular test, the delayed matching-to-sample task, is performed in a similar manner by both humans and non-human primates. Five young adult macaques were employed in this study, displaying variable capacities for retention in the task. Baseline performance was very consistent and three levels of performance difficulties (95-100%, 80-85% and 65-75% correct choices) were employed by including several delay intervals (0-60 sec) in each session. A reproducible enhancement in performance by nicotine in macaques performing a delayed matching-to-sample task was demonstrated. Nicotine enhanced performance with an average increase of 10% at the longest retention delay interval. This beneficial effect of nicotine was abolished in animals pretreated with a low dose (0.5 mg/kg) of mecamylamine to block central nicotinic receptors. Selective blockade of peripheral nicotinic receptors with hexamethonium was without effect on the nicotine response. A high dose (2 mg/kg) of mecamylamine itself induced a marked inhibition of performance, while an equivalent dose of hexamethonium was without effect. These experiments point to the possibility that central nicotinic receptors may be exploited pharmacologically to enhance memory performance. In this respect it is interesting that nicotine was most effective at enhancing performance when recall was more difficult, that is, on the longer retention interval delays. This could signify that nicotine might be particularly effective in the most impaired individuals. Lastly, it is encouraging that the mecamylamine induced decrease in cognitive performance might provide a new model of memory impairment from which to study the pathogenesis and develop new pharmacological strategies for the dementias.

Animals↗

PubMed1995

Structured observation of motor performance (SOMP-I) applied to neonatally healthy fullterm infants at the ages of 0-10 months.

A new protocol for structured observation of motor performance in infants, SOMP-I, was applied to 72 neonatally healthy fullterm infants at 0, 2, 4, 6 and 10 months of age. It contains 13 items, formed as ascending scales, consisting of detailed descriptions of motor performance in different body positions and body parts. The observed motor performance is assessed regarding level of development (progress), and degree and type of deviation from the described performance (quality). When observed according to the new protocol, the infants' motor performance corresponded to higher levels of motor development with increasing age and agreed with descriptions in other standardized developmental scales. With age, the motor performance observed was distributed over more levels in the different scales and the number of infants with deviations from the described performance increased in most positions, but decreased in the prone position. The item for the head, at 2 months, showed the largest number of infants with deviations. The total number of deviations in each infant was small. In conclusion, the SOMP-I protocol can describe motor performance in a group of infants who were healthy at birth and is detailed enough to identify differences regarding progress of motor development and quality of motor performance. The assessment is easily performed.

Aging↗

PubMed2004

Improving anesthesiologist performance through profiling and incentives.

STUDY OBJECTIVE: To determine the influence of profiling and incentives on anesthesiologist behavior in relation to several key indicators of performance. DESIGN: Prospective collection and analysis of operational data before and after implementation of a physician profiling, reporting, and incentive program. SETTING: University hospital. MEASUREMENTS: An intervention consisting of two components was studied with the intent of stimulating a high level of performance in relation to a peer group. The first component, a monthly report of physician performance via an individualized performance report, was provided to each physician for each of 6 months. The second component consisted of a financial incentive. For each month in the study, physicians were eligible to receive a variable financial incentive of between $0 and $500 per month depending on individual performance based scoring in relation to each other. Physician performance was tracked in five areas: 1) percentage of first cases of the day in the room at or before the scheduled in-room time, 2) percentage of cases with an anesthesia prep time less than a target, 3) percentage of cases delayed due to waiting for an anesthesiology patient evaluation, 4) percentage of cases delayed during the anesthesiology controlled time, and, 5) percentage of cases delayed due to waiting for the anesthesiology attending. Results were reported to each physician on a monthly basis, by e-mail distribution, of an individualized perioperative efficiency summary report. A monthly financial incentive was awarded to the top performing physicians in the form of a credit to the physician's personal CME/expense account. Also, all physicians received a rank order list of their performance on each indicator at the end of each month. MAIN RESULTS: 31 anesthesiologists, comprising the multispecialty division, and covering all services with the exception of obstetrics, pediatrics, and cardiothoracic anesthesia were tracked for 6 months. Compared to the first month, the percent of first cases of the day in the room at or before the scheduled start time and the percent of cases with an anesthesiology prep time less than target increased significantly (19 +/- 4.6%, vs. 61 +/- 6.5%, 95% CI, p <0.001; and 57 +/- 5.3%, vs. 73 +/- 5.1%, 95% CI, p <0 .001) during the sixth month. The mean number of cases per physician with a delay during anesthesiology controlled time decreased (14.9 +/- 2.9 vs. 3.3 +/- 1, p <0.001), no change occurred in the number of cases with a delay due to waiting for an anesthesiology patient evaluation or number of cases delayed due to waiting for the anesthesiology attending in the sixth month compared with the first month. CONCLUSION: Tracking and rewarding physician performance with monthly profiling and a financial incentive given to the best in a peer group improves anesthesiologist performance in several key areas.

Anesthesiology↗

PubMed2005

Optical performance of 3 intraocular lens designs in the presence of decentration.

PURPOSE: To study the theoretical optical performance of 3 intraocular lens (IOL) designs in the presence of IOL decentration. SETTING: Optics Center, Bausch & Lomb, Rochester, New York, USA. METHODS: A ray-tracing program was used to evaluate the effect of IOL decentration on the optical performance of 3 silicone IOLs (LI61U, Bausch & Lomb; Tecnis Z9000, Advanced Medical Optics; and a new aberration-free IOL [SofPort AO, Bausch & Lomb]) in an experimental model eye. The study was done using pupil diameters of 3.0 mm, 4.0 mm, and 5.0 mm and IOL decentrations of 0 mm, 0.25 mm, 0.50 mm, 0.75 mm, and 1.00 mm. The modulation transfer functions were computed and plotted. A Monte Carlo simulation analysis with 1000 trials with IOL decentration randomly varying for each pupil size was performed. RESULTS: Decentration of LI61U and Tecnis Z9000 IOLs led to asymmetrical higher-order aberrations that adversely affected the optical performance of the model eye; performance was not affected with the aberration-free IOL because it lacks inherent spherical aberration. Optical performance with the aberration-free IOL was better than with the LI61U IOL as the former has less spherical aberration and did not introduce other aberrations when decentered. Performance with the aberration-free IOL was better than with the Tecnis Z9000 IOL for 3.0 mm, 4.0 mm, and 5.0 mm pupils when decentration exceeded 0.15 mm, 0.30 mm, and 0.38 mm, respectively. Performance with the LI61U IOL was better than with the Tecnis Z9000 IOL for 3.0 mm, 4.0 mm, and 5.0 mm pupils when decentration exceeded 0.3 mm, 0.5 mm, and 0.5 mm, respectively. Monte Carlo simulations showed the expected postoperative results of the LI61U IOL and aberration-free IOL would be repeatable and predictable, whereas the outcomes with the Tecnis Z9000 IOL would vary widely. CONCLUSIONS: The optical performance of the model eye was not affected by decentration of an aspheric IOL designed to have no inherent spherical aberration. With decentration, the performance with the new IOL was better than with a conventional spherical IOL and an aspheric IOL designed to offset the spherical aberration of an average cornea.

Biocompatible Materials↗

PubMed2006

Effects of visual feedback on manipulation performance and patient ratings.

OBJECTIVE: This study examined the explicit targeted outcome (a criterion standard) and visual feedback on the immediate change in and the short-term retention of performance by novice operators for a high-velocity, low-amplitude procedure under realistic conditions. METHODS: This study used a single-blind randomized experimental design. Forty healthy male (n = 26) and female (n = 14) chiropractic student volunteers with no formal training in spinal manipulative therapy participated. Biomechanical parameters of an L4 mammillary push spinal manipulation procedure performed by novice operators were quantified. Participants were randomly assigned to 2 groups and paired. One group received visual feedback from load-time histories of their performance compared with a criterion standard before a repeat performance. Participants then performed a 10-minute distractive exercise consisting of National Board of Chiropractic Examiners review questions. The second group received no feedback. An independent rating of performance was conducted for each participant by his/her partner. Results were analyzed separately for biomechanical parameters for partner ratings using the Student t test with levels of significance (P < .01) adjusted for repeated testing. RESULTS: Expressed in percent change for each individual, visual feedback was associated with change in the biomechanical performance of group 2, a minimum of 14% and a maximum of 32%. Statistical analysis rating of the performance favored the feedback group on 4 of the parameters (fast, P < .0008; force, P < .0056; precision, P < .0034; and composite, P < .0016). CONCLUSION: Quantitative feedback, based on a tangible conceptualization of the target performance, resulted in immediate and significant improvement in all measured parameters. Newly developed skills were retained at least over short intervals even after distractive tasks. Learning what to do with feedback on one's own performance may be more important than the classic teaching of how to do it.

Adult↗

PubMed2005

Carboplatin-based chemotherapy in patients with advanced non-small cell lung cancer and a poor performance status.

BACKGROUND: Poor performance status patients with advanced non-small cell lung cancer (NSCLC) have frequently been excluded from clinical trials due to the perception that they would have excessive treatment-related toxicity and a limited life expectancy. METHODS: A retrospective review of two multicenter trials centered at the University of North Carolina of patients who were treated with platinum-based chemotherapy for advanced NSCLC was conducted. Patients were divided into two subgroups based on Karnofsky performance status (KPS). Patients with a KPS = 70 were considered to have poor performance status, while patients with a KPS > or =80 were considered to have good performance status. RESULTS: Of the 387 patients, 19% (n = 73) had a poor performance status. The response rate (complete and partial responses) was similar between the two sub-groups (26% versus 28%); however, there was a difference in survival (p = 0.0004, log-rank test) between the groups. The median survival and 1-year survival rate for the poor performance status patients was 4.9 months and 21%, while the good performance status patients had a median survival of 8.4 months and a 1-year survival rate of 31%. The rate of National Cancer Institute (NCI) Common Toxicity Criteria (CTC) toxicities was similar between the two groups (p = 0.33). The percentage of patients receiving <4 cycles of therapy in the poor and good performance status was 55 and 39%, respectively (p = 0.012). CONCLUSIONS: Patients with poor performance status treated with platinum based chemotherapy have a similar rate of toxicity compared to good performance status patients. Their overall survival was lower despite a similar response to chemotherapy.

Antineoplastic Agents↗