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Occupant perception of indoor air and comfort in four hospitality environments.

This article reports on a survey of customer and staff perceptions of indoor air quality at two restaurants, a billiard hall, and a casino. The survey was conducted at each environment for 8 days: 2 weekend days on 2 consecutive weekends and 4 weekdays. Before and during the survey, each hospitality environment satisfied ventilation requirements set in ASHRAE Standard 62-1999, Ventilation for Acceptable Indoor Air. An objective of this study was to test the hypothesis: If a hospitality environment satisfies ASHRAE ventilation requirements, then the indoor air is acceptable, that is, fewer than 20% of the exposed occupants perceive the environment as unacceptable. A second objective was to develop a multiple regression model that predicts the dependent variable, the environment is acceptable, as a function of a number of independent perception variables. Occupant perception of environmental, comfort, and physical variables was measured using a questionnaire. This instrument was designed to be efficient and unobtrusive; subjects could complete it within 3 min. Significant differences of occupant environment perception were identified among customers and staff. The dependent variable, the environment is acceptable, is affected by temperature, occupant density, and occupant smoking status, odor perception, health conditions, sensitivity to chemicals, and enjoyment of activities. Depending on the hospitality environment, variation of independent variables explains as much as 77% of the variation of the dependent variable.

Air Pollution, Indoor↗

Assessment of neutrophil aggregation by Coulter STKR and STKS haematological analysers.

We have studied an alternative method to aggregometry for the assessment of human polymorphonuclear (PMN) leucocyte aggregation. This simple, rapid and reliable procedure counts unaggregated cells on both Coulter STKS and STKR haematological analysers by the impedance principle. Aggregation of PMN was induced by 15 min incubation with fresh autologous serum (FAS) after a 10 min phorbol myristate acetate (PMA) activation of neutrophils in small aliquots (0.25 ml) of suspension containing about 4.0 x 10(9) PMN/1. Differences (x 100) between count of resting and PMA+FAS treated neutrophils/count of resting PMN reflect percent aggregation. By this procedure, PMN aggregation did not occur in autologous plasma from EDTA anticoagulated whole blood; it was partially inhibited by hydrocortisone, whereas inactivated or Zymosan activated sera gave values similar to those from FAS induced aggregation. PMA aggregation was dependent on Ca2+ + Mg2+ concentration. Intra-assay analytical variability did not exceed 4% on either instrument. Reference values (n = 20) of percent PMN aggregation were 50.7 +/- 4.7 on STKS and 47.1 +/- 4.8 on STKR. Most probably, the interindividual variance was due to the physiological variability of Mg2+ and/or Ca2+ concentrations in FAS. Thus, this procedure reflects the true PMN aggregability status in a given subject, and in a given electrolyte environment.

Adult↗

Evaluation of a blood gas and chemistry monitor for use during surgery.

An observational study was performed to evaluate a new blood gas and chemistry monitor (GEM-6 Diamond Sensor Systems, Ann Arbor, Michigan) in nine patients during cardiac surgery. Paired blood samples were analyzed by the instrument under test and by standard clinical laboratory instruments. The differences between the measurements of the new and the standard instruments are summarized as follows (mean +/- standard deviation, units of measure, number of samples): pH (-0.039 +/- 0.02, 154); PCO2 (2.63 +/- 1.8 mmHg, 154); venous PO2 (-2.0 +/- 3.0 mmHg, 72), hematocrit (4.7 +/- 2.7%, 98), potassium (0.18 +/- 0.13 mmol, 100), and ionized calcium (0.195 +/- 0.11 mmol, 100). Because the differences in arterial PO2 measurements were markedly heteroscedastic, a logarithmic transformation was employed, which upon retransformation gave the test instrument's 95% confidence limits as within 5.1% below to 46% above the nominal value on 82 samples. However, on the 14 samples having nominal values below 165 mmHg (the upper limit of the calibrated range of the GEM-6) the 95% confidence limits were from 5.4% below to 23.6% above the nominal reading. No failures of the test instrument occurred during the evaluation, and quality control standards run before, midway through, and again after sampling from each patient all gave readings within the manufacturer's tolerance. For all variables except hematocrit and ionized calcium, this instrument matches the values from the laboratory well enough over the clinically important range to supplant it for intraoperative monitoring purposes.

Acid-Base Equilibrium↗

The Psychogeriatric Assessment Scales (PAS): psychometric properties in French and German speaking populations.

OBJECTIVES: To investigate the structure and measurement properties of the Psychogeriatric Assessment Scales (PAS) in a community sample, to study the performance of French and German translations of the PAS, and to determine the power of PAS scales to discriminate dementia and depression diagnosed to DSM-IV criteria. Design and measures The measures were gathered as part of a large community survey. Responses to PAS items were obtained in the course of the administration of the 'Canberra Interview for the Elderly'. Demographic variables, the mini-mental state examination and measures of premorbid intelligence robust to current intellectual impairment were also gathered in the course of the survey. SETTING: A community survey in the cities of Zurich and Geneva, Switzerland. PARTICIPANTS: Subjects were residents of the two cities aged 65 years or older. There were 465 participants from Zurich and 456 from Geneva. Interviews with an informant who knew the subject well were also obtained. Subjects from Zurich were interviewed in German, subjects from Geneva in French. RESULTS: Confirmatory factor analyses of PAS scales showed close agreement between sites and with results obtained in the sample used to construct the instrument. Correlations with demographic and validating variables also showed this pattern. The PAS cognitive impairment and cognitive decline scales were shown to be good discriminators of DSM-IV dementia while the depression scale discriminated DSM-IV major depressive episode. CONCLUSIONS: This study supports the PAS as a valid and reliable summary of the status of older persons with respect to the impairments, changes and symptomatology that lie at the core of dementing and depressive disorders. This study not only supports the results found in the original development sample, but demonstrates that it performs well against DSM-IV diagnostic criteria and amongst speakers of French and German.

Aged↗

The use of screening instruments for the detection of dementia.

Dementia is a clinical and public health issue of growing importance as life expectancy increases across the planet. Despite advances in both genetic research and clinical management strategies, neither cure nor primary prevention is currently feasible. However, screening for dementia is critical for secondary prevention, i.e., early diagnosis and treatment as well as disability limitation and prevention of complications. Screening is also important for community surveillance and the planning of health and human services. The most appropriate screening approach for a particular clinical or research setting should be selected on the basis of the purpose of screening in that setting. Ideally, all elderly individuals, as well as younger persons with known risk factors, should be routinely screened for dementia. Availability of staff resources, including time and skills, should also be taken into account. Objective cognitive testing appears to be the most logical approach to screening for dementia. However, potential confounding variables and psychometric properties of the instruments should be considered. Ancillary measures such as functional disability scales, self-reported cognitive functioning, and informants' perceptions may usefully supplement (or supplant) cognitive testing in certain populations. The limitations of screening should be recognized.

Aged↗

Facilitation of instrumental behavior by a Pavlovian appetitive conditioned stimulus.

Three experiments examined appetitive Pavlovian-instrumental interactions by presenting separately trained conditioned stimuli (CSs) during reinforced instrumental responding in rabbits. Intra-oral reinforcement was used to minimize interference from peripheral responses such as magazine approach. In experiment 1, the rabbits were first trained to perform an instrumental head-raising response for sucrose reward. A conditioned jaw movement response was then established to a 2-sec CS by pairing it with sucrose; a control stimulus was unpaired with sucrose. Instrumental responding maintained by a variable-interval 40-sec schedule was enhanced during 10-sec presentations of the paired, but not the unpaired, CS. Responding on a variable-ratio 15 schedule was unaffected except on trials on which the pre-CS baseline response rate was low; in such cases the paired CS caused a long-lasting acceleration of responding. Noncontingent presentation of the sucrose reinforcer itself briefly suppressed responding but had no long-term effect. In Experiment 2, a CS that had been conditioned at a 10-sec duration produced the same pattern of effects as in the first study, indicating that facilitation resulted from CS presentation rather than from the frustrative effects of non-reinforcement of the CS. In Experiment 3 an inhibitory CS blocked facilitation by the excitatory CS but did not itself affect instrumental responding. These results support the view that Pavlovian processes play a positive role in instrumental performance and suggest that previous findings of suppression by a short-duration CS reflect peripheral interference. The dependence of facilitation on the baseline level of responding is discussed in terms of associative and motivational theories of Pavlovian mediation.

Animals↗

Order effects in the assessment of quality of life in cancer patients.

Methodological studies and outcome research often include several health-related quality of life (HRQoL) measurement scales in one questionnaire. Psychological studies have previously demonstrated that changing the sequential order of measurement scales within a questionnaire can alter the pattern of responses. Little is known, however, about whether there are order effects on the assessment of HRQoL in cancer patients. Here we address this issue in a study of 190 Singaporean cancer patients who were assessed using two different HRQoL instruments placed in alternating sequence within a questionnaire package. Measurement properties of the instruments, including the number of missing values, means, variability, known-group validity and internal consistency, were compared in the two samples representing different presentation orders. The HRQoL instruments administered in different sequential orders appeared to be equivalent in several aspects. No major effect of presentation order on outcomes was shown. The reasons and implications of the absence of an order effect are discussed. We conclude that presentation order is unlikely to alter the responses to the two HRQoL instruments.

Analysis of Variance↗

Analytical performance and comparability of the determination of triglycerides by 12 Lipid Research Clinic laboratories.

Twelve Lipid Research Clinic laboratories performed automated fluorometric triglyceride analyses on four control serum pools of known concentration by a modified Hantzsch reaction. The analyses were done during a two-year period, with use of common standards, methodology, and quality-control procedures. Estimates of analytical bias, variability, and short- and long-term trends for each instrument and for the entire group of LRC instruments are presented. High accuracy, precision, and interlaboratory comparability were achieved through rigorous standardization and control of the entire analytical procedure. Individual instrument biases varied from an average of 4.9% below to 1.0% above reference values. Between-run variability was often less than within-run variability and interlaboratory variation was substantially less than intralaboratory variation. The total standard deviation for all instruments ranged from 37 to 63 mg/liter. Only 5 to 14% of this variation was due to differences among instruments. The among-instruments standard deviation ranged from 12 to 17 mg/liter; the between-run, within-instrument standard deviation ranged from 29 to 46 mg/liter, and within-run standard deviation from 27 to 40 mg/liter. The significance of the results for long-term collaborative studies is discussed.

Analysis of Variance↗

Selective tomographic imaging of patients with new-onset seizure disorders.

OBJECTIVE: Significant benefit could be realized by developing a clinical decision rule for new-onset seizure victims that would be capable of discriminating between patients having relevant structural lesions visible on computed tomographic (CT) imaging and those who do not. This study sought to determine whether a reliable decision rule could be developed using a limited number of clinical and demographic characteristics. METHODS: Chi-squared recursive partitioning was applied in a secondary analysis of the EMERGEncy ID NET database of new-onset seizure victims. Variables in this database (age, sex, race, ethnicity, seizure type, history of HIV or cysticercosis, and presence or absence of lateralizing neurologic findings or altered mentation) provided the partitioning variables, while CT imaging results provided outcome measures. The study sought to develop a decision rule with 100% sensitivity for detecting any intracranial lesions, and a separate rule with 100% sensitivity for detecting lesions of emergent concern. RESULTS: A decision rule using age > or = 65 years, lateralizing neurologic findings, altered mentation, high risk or known HIV infection, history of cysticercosis, and Hispanic ethnicity showed a sensitivity of 91.9% [95% confidence interval (95% CI) = 88.8% to 94.9%] in detecting individuals who had any tomographic finding. This rule had a sensitivity of 90.1% (95% CI = 83.4% to 96.7%) in detecting individuals with emergent tomographic findings. CONCLUSIONS: Recursive partitioning failed to produce a decision rule capable of reliably identifying new-onset seizure patients who have important lesions identified on CT. Future attempts to formulate such an instrument may need to include additional variables. In the interim, physicians should use liberal tomographic imaging in evaluating patients who present with new-onset seizures.

Acute Disease↗

Somatisation in primary care: clinical judgement and standardised measurement compared.

BACKGROUND: In daily practice general practitioners (GPs) generally rely on their clinical judgement in assessing whether patients somatise distress. Nevertheless, conclusions derived from research on somatisation in primary care are largely based on standardised measurements of somatisation. We investigated the relation between GPs' clinical judgement of somatisation and a somatisation research instrument (DSM-III-R), and examined how both operationalisations of somatisation related to other important variables. METHODS: In nine general practices, 407 frequently attending patients answered a questionnaire on somatisation symptoms, while the GPs gave their judgement on somatisation and communication for each patient. Other variables were extracted from the registered health status of the patients. RESULTS: We found a weak association (correlation: 0.27) between the GPs' judgement and the research instrument; however, relations with other variables showed that both operationalisations were very similar constructs. The research instrument incorporated more psychological problems (depression and anxiety), while the GPs' judgement of somatisation was more influenced by attendance rate and by aspects of communication with the patient. CONCLUSION: For research addressing somatisation in primary care as a practical clinical problem, the operationalisation of somatisation should include the clinical judgement of the practitioner as well, thereby widening the focus from co-morbid mental disturbances to communication aspects.

Adult↗

Interbody fusion and instrumentation.

Fusion indications in adult degenerative disk disease of the lumbosacral spine include isolated disk resorption, primary and secondary instability, recurrent disk herniation, and pseudarthrosis. Common to these indications are variable proportions of biomechanical insufficiency of the motion segment, instability, deformity, and spinal stenosis. Apart from favorable psychosocial and work related variables, satisfactory outcome is dependent on treatment by a combination of diskectomy, decompression, and deformity correction, in addition to fusion. Isolated intertransverse or interbody fusions show variable fusion rates that are increased by concurrent instrumentation. Persistent pseudarthrosis rates and instrumentation failures have prompted circumferential fusion techniques. Posterior lumbar interbody fusion (PLIF) and segmental pedicle-based plate fixation overcome earlier problems with PLIF by allowing for wide decompression and increased exposure for disk space preparation, minimizing neural injury. Pedicle fixation restores segmental stability and minimizes graft retropulsion. Restoration of anterior column support prolongs instrumentation life, and increases fusion rates irrespective of the number of levels fused. Disk space distraction, with the use of instrumentation as a working tool, permits safer decompression of the intraforaminal zone, a common area of stenosis, and single or multilevel deformity correction to restore coronal, axial, and sagittal alignment and spinal balance. Even though the surgical technique is demanding, fusion rates up to 96% and clinical success up to 86% are achieved.

Adult↗

The influence of a mouthpiece and noseclip on breathing pattern at rest is reduced at high altitude.

The effects of the instrumentation by a mouthpiece (MP) and a noseclip (NC) on the ventilatory response to short time hypobaric hypoxia were studied in 10 healthy volunteers at rest. The subjects were exposed to simulated altitude of 500 m, 3000 m, 4000 m and again 500 m, each altitude being applied for 30 min in a hypobaric chamber. Resting minute ventilation (VE), tidal volume (VT) and respiratory frequency (fR) using inductive plethysmography were continuously measured in all subjects in a standardized half lying position. The recordings were carried out at each altitude during the first 10 min without MP and NC, then 10 min with them, and the last 10 min again without them. At 500 m during MP+NC breathing VE and VT were increased, whereas fR was not significantly changed. At 3000 m, the VE increase with MP+NC was no more significant and fR was decreased. These effects of MP+NC on respiration disappeared at 4000 m and reappeared after the descent to 500 m. Furthermore, with and without MP and NC the variability of VE at 4000 m was significantly higher than at 500 m before ascent, and in all altitudes the variability of VT was significantly reduced by the MP+NC. It is concluded that the influence of MP+NC on VE, VT and fR is reduced or even abolished at high altitude, whereas the hypoxia induced increase of VE variability is not affected by the instrumentation.

Acclimatization↗

Development of a multidimensional labour satisfaction questionnaire: dimensions, validity, and internal reliability.

BACKGROUND: No published quantitative instrument exists to measure maternal satisfaction with the quality of different models of labour care in the UK. METHODS: A quantitative psychometric multidimensional maternal satisfaction questionnaire, the Women's Views of Birth Labour Satisfaction Questionnaire (WOMBLSQ), was developed using principal components analysis with varimax rotation of successive versions. Internal reliability and content and construct validity were assessed. RESULTS: Of 300 women sent the first version (WOMBLSQ1), 120 (40%) replied; of 300 sent WOMBLSQ2, 188 (62.7%) replied; of 500 women sent WOMBLSQ3, 319 (63.8%) replied; and of 2400 women sent WOMBLSQ4, 1683 (70.1%) replied. The latter two versions consisted of 10 dimensions in addition to general satisfaction. These were (Cronbach's alpha): professional support in labour (0.91), expectations of labour (0.90), home assessment in early labour (0.90), holding the baby (0.87), support from husband/partner (0.83), pain relief in labour (0.83), pain relief immediately after labour (0.65), knowing labour carers (0.82), labour environment (0.80), and control in labour (0.62). There were moderate correlations (range 0.16-0.73) between individual dimensions and the general satisfaction scale (0.75). Scores on individual dimensions were significantly related to a range of clinical and demographic variables. CONCLUSION: This multidimensional labour satisfaction instrument has good validity and internal reliability. It could be used to assess care in labour across different models of maternity care, or as a prelude to in depth exploration of specific areas of concern. Its external reliability and transferability to care outside the South West region needs further evaluation, particularly in terms of ethnicity and social class.

Female↗

Lumbar and lumbosacral fusion using Steffee instrumentation.

Posterior and posterolateral spinal fusion with the Steffee variable plating system have been performed on 176 patients at Walter Reed Army Medical Center since November 1985. This report covers the authors' early experience using the Steffee device on 39 patients. All of the 39 patients (100%) were available for a minimum follow-up of 2 years. Complications occurred in 26% of the patients. Radiographic pseudarthrosis occurred in 8% of the patients. The findings suggest that lumbar and lumbosacral fusion supplemented with Steffee plate instrumentation are associated with a low incidence of pseudarthrosis and acceptable morbidity overall.

Adult↗

Inter-device reproducibility of the scanning laser polarimeter with variable cornea compensation.

OBJECTIVE: To evaluate the interdevice reproducibility of retinal nerve fibre layer (RNFL) thickness measurements obtained with the commercially available GDx-VCC, a scanning laser polarimeter with variable (individualized) corneal compensation. METHODS: A prospective instrument validation study in which 13 GDx-VCC devices were tested. One eye each, from three normal subjects were used to test each of the devices, on the same day, by an experienced operator. Variability and reproducibility for each of five GDx parameters were calculated. RESULTS: For each of five tested GDx parameters, the coefficient of variation and 95% confidence interval range (microm), for the 13 devices, respectively, were: TSNIT avg: 5.1%, 3.84 microm; Superior avg: 5.3%, 4.82 microm; Inferior avg: 6.1%, 5.50 microm; TSNIT standard deviation: 8.6%, 2.92 microm; and nerve fibre indicator (NFI): N/A, 5.69. Item reliability (Cronbach's alpha) for the five GDx parameters are: TSNIT-Avg: 0.97, Sup-Avg: 1.00, Inf-Avg: 0.84, TSNIT-SD: 0.99, NFI: 0.99. CONCLUSIONS: With the commercially available GDx-VCC, our results indicate that RNFL measurements appear reproducible across devices.

Adult↗

The usefulness of a predictive instrument to reduce inappropriate admissions to the coronary care unit.

A mathematical instrument was developed to supplement the diagnostic information available to physicians in the emergency room to improve physicians' diagnostic accuracy in managing patients with acute ischemic heart disease and thereby reduce inappropriate coronary care unit admissions. The instrument was empirically derived and is based on nine clinical, historical, and electrocardiographic predictive variables. Probabilities of acute ischemic heart disease generated by the instrument were given to the house staff in an emergency room during alternate months. Comparison of the control months (455 patients) with the experimental months (401 patients) showed the following: The overall diagnostic accuracy increased from 83% to 91% (P less than 0.005), the overdiagnostic accuracy increased from 51% to 33% (P less than 0.01), and the admission rate to the coronary care unit fell from 26% to 14% (P less than 0.001), while the inappropriate discharge rate from the emergency room did not change, 3% versus 3% (not significant).

Coronary Care Units↗

A 15-month evaluation of the effects of repeated subgingival minocycline in chronic adult periodontitis.

BACKGROUND: A double-blind, randomized, parallel, comparative study was designed to evaluate the long-term safety and efficacy of subgingivally administered minocycline ointment versus a vehicle control. METHODS: One hundred four patients (104) with moderate to severe adult periodontitis (34 to 64 years of age; mean 46 years) were enrolled in the study. Following scaling and root planing, patients were randomized to receive either 2% minocycline ointment or a matched vehicle control. Study medication was administered directly into the periodontal pocket with a specially designed, graduated, disposable applicator at baseline; week 2; and at months 1, 3, 6, 9, and 12. Scaling and root planing was repeated at months 6 and 12. Standard clinical variables (including probing depth and attachment level) were evaluated at baseline and at months 1, 3, 6, 9, 12, and 15. Microbiological sampling using DNA probes was done at baseline; at week 2; and at months 1, 3, 6, 9, 12, and 15. RESULTS: Both treatment groups showed significant and clinically relevant reductions in the numbers of each of the 7 microorganisms measured during the entire 15-month study period. When differences were detected, sites treated with minocycline ointment always produced statistically significantly greater reductions than sites which received the vehicle control. For initial pockets > or =5 mm, a mean reduction in probing depth of 1.9 mm was seen in the test sites, versus 1.2 mm in the control sites. Sites with a baseline probing depth > or =7 mm and bleeding index >2 showed an average of 2.5 mm reduction with minocycline versus 1.5 mm with the vehicle. Gains in attachment (0.9 mm and 1.1 mm) were observed in minocycline-treated sites, with baseline probing depth > or =5 mm and > or =7 mm, respectively, compared with 0.5 mm and 0.7 mm gain at control sites. Subgingival administration of minocycline ointment was well tolerated. CONCLUSIONS: Overall, the results demonstrate that repeated subgingival administration of minocycline ointment in the treatment of adult periodontitis is safe and leads to significant adjunctive improvement after subgingival instrumentation in both clinical and microbiologic variables over a 15-month period.

Adult↗

Measurement of drinking behavior using the Form 90 family of instruments.

Although drinking behavior is clearly a central dependent variable in alcoholism treatment research, the field has reached no consensus on measurement methodology for alcohol consumption. At least four methods for quantifying consumption have been commonly used in outcome studies: quantity-frequency questions, average consumption grids, timeline follow-back and self-monitoring. The Form 90 family of structured interviews was developed by collaboration among the Project MATCH investigators, combining the strengths of prior assessment methodologies. The development, structure, supporting software and training approaches for the Form 90 instruments are described.

Alcohol Drinking↗