Feasibility and reliability of body composition measurements in adults with severe intellectual and sensory disabilities.

BACKGROUND: Anthropometric measurements are widely used to reliably quantify body composition and to estimate risks of overweight in healthy subjects and in patients. However, information about the reliability of anthropometric measurements in subjects with severe intellectual and sensory disabilities is lacking. OBJECTIVE: The purpose of this study was to determine the feasibility and the test-retest reliability of body composition measures in subjects with severe intellectual and sensory disabilities. METHOD: The study population consisted of 45 subjects with severe intellectual and sensory disabilities. Body mass index, waist circumference, skin folds and tibia length were measured. Reliability was assessed by Wilcoxon signed rank test, limits of agreement (LOA) and intraclass correlation coefficients. The outcomes were compared with values provided by the World Health Organization. RESULTS: There were no significant differences between test and retest (P < 0.05). For the skinfold measurements, however, the LOA was insufficient. Intraclass correlation coefficients for all variables, except skinfold measurements, were 0.90 or above. CONCLUSION: Test-retest reliability and feasibility for all measurements are acceptable in subjects with severe intellectual and sensory disabilities. Skinfold measurements, however, could not be reliably performed in these subjects. Measuring tibia length and using the determined formula to calculate body height from tibia length is a reliable alternative for measuring body height. Although measuring the body height of subjects with severe disabilities was feasible, measuring tibia length was more feasible.

Patient satisfaction with occupational health physicians, development of a questionnaire.

AIMS: To develop a questionnaire that measures specific aspects of patient satisfaction with occupational health physicians. METHODS: General patient satisfaction questionnaires, a literature survey, and interviews with patients were used. An initial questionnaire was distributed among sick listed patients (n = 432) of occupational physicians (n = 90) from different occupational health services. To reduce items and to develop scales exploratory factor analysis and reliability analysis was used. A linear regression model was used to predict satisfaction ratings from the scales of the questionnaire. RESULTS: Questions about independence of the occupational physician were difficult to ask unambiguously. The factor analysis revealed five relevant factors which were named "being taken seriously as a patient", "attitude towards occupational health services", "trust and confidentiality", "expectations", and "comfort and access". All scales could be reduced to a maximum of five items without reducing the scale reliability too much. In the regression analysis, 71% of the variance of satisfaction ratings was explained by the first four scales and most by the first scale. "Comfort and access" did not contribute significantly to the model. CONCLUSIONS: A short questionnaire was developed to measure different aspects of patient satisfaction specific for occupational health. Whether the questionnaire can effectively lead to quality improvement in occupational health services should be investigated.

Relation between indicators for quality of occupational rehabilitation of employees with low back pain.

OBJECTIVES: To assess if the implementation of guidelines for occupational rehabilitation of patients with low back pain by means of process variables--a set of objective criteria for technical performance and continuity of care--led to a better outcome in clinical and return to work variables. METHODS: The study group consisted of 59 patients with at least 10 days of sick leave because of low back pain. Univariate analyses as well as multiple logistic regression and Cox's regression analyses were performed to assess the relation between quality of care and outcome. RESULTS: Process indicators for technical competence, continuity of care, and total performance were all significantly related to satisfaction of employees. Continuity of care and total performance were significantly related to working status at 3 months, and time to return to work. None of the process indicators was related to pain or disability after 3 months follow up. Satisfaction was not related to any of the other outcome variables. This indicates that if guidelines for occupational rehabilitation are met, outcome is better. CONCLUSION: Quality of the process of care was related to outcome. Interventions of occupational physicians need improvement in the areas of continuity of care and communication with treating physicians. The effectiveness of an improved intervention should be studied in a subsequent randomised clinical trial.

Evaluation research in occupational health services: general principles and a systematic review of empirical studies.

OBJECTIVES: To study the nature and extent of evaluation research in occupational health services (OHSs). METHODS: Literature review of evaluation research in OHSs. On the basis of a conceptual model of OHS evaluation, empirical studies are categorised into aspects of input, process, output, outcome, and OHS core activities. RESULTS: Many methods to evaluate OHSs or OHS activities exist, depending on the objective and object of evaluation. The amount of empirical studies on evaluation of OHSs or OHS activities that met the non-restrictive inclusion criteria, was remarkably limited. Most of the 52 studies were more descriptive than evaluative. The methodological quality of most studies was not high. A differentiated picture of the evidence of effectiveness of OHSs arises. Occupational health consultations and occupational rehabilitation are hardly studied despite much time spent on the consultation by occupational physicians in most countries. The lack of effectiveness and efficiency of the pre-employment examination should lead to its abandonment as a means of selection of personnel by OHSs. Periodic health monitoring or surveillance, and education on occupational health hazards can be carried out with reasonable process quality. Identification and evaluation of occupational health hazards by a workplace survey can be done with a high output quality, which, however, does not guarantee a favourable outcome. CONCLUSIONS: Although rigorous study designs are not always applicable or feasible in daily practice, much more effort should be directed at the scientific evaluation of OHSs and OHS instruments. To develop evidence-based occupational health care the quality of evaluation studies should be improved. In particular, process and outcome of consultation and rehabilitation activities of occupational physicians need to be studied more.

Prognostic factors for chronic disability from acute low-back pain in occupational health care.

OBJECTIVES: This study attempted to determine the prognostic indicators of low-back pain in an occupational health setting. METHODS: The identification of prognostic factors of (i) functional disability after 3 months' follow-up, (ii) functional disability after 12 months' follow-up, and (iii) time to return to work among 120 workers who reported to an occupational health unit and were off work with low-back pain for at least 10 days. Crude and adjusted odds ratios and hazard ratios with 95% confidence intervals were estimated for the 3 outcome measures. RESULTS: Factors related to a longer time to return to work were radiating pain, high functional disability at the beginning of the study, problems in relations with colleagues, and high work tempo and work quantity. High functional disability at the beginning of the study and a high avoidance coping style predicted functional disability at 3 months. Functional disability at 12 months was more accurately predicted by work-related and psychosocial factors. CONCLUSIONS: Especially radiating pain and functional disability predict a long duration of low-back pain in occupational health practice. Occupational physicians should also note work-related and psychosocial characteristics.

Development and evaluation of a quality assessment instrument for occupational physicians.

OBJECTIVES: To develop and apply a method for assessing the quality of the process of occupational health care for individual patients. METHODS: The scientific literature was studied to develop a method to assess the quality of the process of occupational rehabilitation for workers with low back pain. The method was applied to health care and university workers with low back pain who were rehabilitated by their occupational physicians. RESULTS: Assessment of quality of care is regarded as a four step approach. Firstly, guidelines should be developed and implemented. Secondly, indicators for quality and criteria to demarcate good and deviant quality were derived from the guidelines. Thirdly, a method for data collection was chosen. Finally, quality was scored. For occupational rehabilitation, there was some deviance from the guidelines for most cases, especially in continuity of care with a deviant rate of 47%. Other indicators deviated from 1.4%-17.4%. Occupational physicians agreed on the relevance of the indicators and criteria, but for three indicators they evaluated the criteria as too rigid. They did not agree with their own performance scores in 66% of the deviant cases. CONCLUSION: Assessing the quality of the process of occupational health care with this method is an asset to present methods, but more specific criteria are needed for a more sensitive assessment.

An audit of occupational health care for employees with low-back pain.

Guidelines for occupational rehabilitation of workers with low-back pain were developed as part of a larger study. We have formulated criteria for good practice of occupational rehabilitation on the basis of these guidelines. To assess the quality of occupational rehabilitation in the Netherlands, these criteria were subsequently used in an audit of medical records. The number of patients who received care consistent with the guidelines was compared to the number of patients eligible to receive that kind of care (performance rate). Six performance rates were calculated from the medical files of 40 workers with 48 new episodes of low-back pain. Two performance rates proved to be below 25% and two almost 50%. The highest performance rate, that for curative policy was 90%. These results are discussed in the light of the reliability of the original data. We recommend construction of guidelines as well as reliable registration of the occupational rehabilitation process to increase the possibilities of auditing and to raise the quality of occupational health care.

Vocational outcome of intervention for low-back pain.

Practical management guidelines for occupational health physicians are needed for the individual support of employees with low-back pain. In this study the level of evidence regarding the efficacy of intervention with vocational outcome parameters was assessed. In a systematic literature search, 40 randomized clinical trials on different types of intervention were retrieved. Their internal validity and statistical power criteria were assessed. The randomization procedure, blinding of patients, and sample size were problematic in most studies. For patients with acute low-back pain limited or moderate evidence was found for the efficacy of no bed rest, a short period of bed rest, and spinal manipulation. For chronic patients limited evidence was found for the efficacy of antidepressants. For the other types of intervention, studies with sufficient statistical power were lacking. Such studies are needed before more-detailed evidence-based guidelines can be formulated for occupational health care.

[Pharmacokinetic and therapeutic monitoring in the development of theophylline-retard preparations]. / Pharmakokinetik und Therapieüberwachung im Rahmen der Entwicklung von Theophyllin-Retard-Präparaten.

After oral application of a sustained release preparation of aminophylline (2 tabl. of 350 mg b. i. d., i. e. a total doses of 1400 mg) the doses related to body mass and the average individual concentration of theophylline in serum are varying about 50% and more of the mean. The mean individual concentration in serum changes proportionally to the doses related to body mass. Furthermore two groups of patients with different theophylline concentrations can be distinguished. The reason is probably a different biotransformation. The mean concentration of theophylline in serum rises to a maximum at the 5th d. From the 8th to the 29th d of treatment the range of concentration is nearly constant. Reaching the steady state is probably overlapped by processes of enzyme induction. In about 60% of the patients the concentrations of theophylline are in the therapeutical range. When adaptation of doses to body mass takes place a higher portion can be expected. To achieve all therapeutical possibilities it is necessary to correct the doses also for the different types of biotransformation.

[Effect and side effects of a depot theophylline preparation within the scope of a clinical trial]. / Wirkung und Nebenwirkung eines Theophyllin-Retard-Präparates im Rahmen der klinischen Prüfung.

Effects and side effects of the Aminophylline-retard-preparation V 37 are studied during a four week period of monotherapy on 50 patients suffering from obstructive lung disease. Treating with a standard dosis (2 X 700 mg daily) the concentrations of Theophylline in serum were in the therapeutical range in 50% of patients. A dosis correction was not proposed. Therefore 9 patients have to be excluded from the trial (5 unsufficient effects, 4 unreasonable side effects). Two further patients must be excluded because of an acute exacerbation of their disease. An optimization of therapy is possible by a stepwise increase of the dosis and by an adaptation of the dosis considering the body weight, the effects (estimating the FEV1) and the side effects. Clinical aspects are more relevant for dosis correction than the estimation of the Theophylline concentration in serum. Its measurement should be performed in special cases.

[Can oscillatory estimation of airway resistance in chronic obstructive patients be improved by the use of double reference resistance?]. / Kann die oszillatorische Einschätzung des Atemwiderstandes chronisch obstruktiver Patienten durch den Einsatz eines verdoppelten Referenzwiderstandes verbessert werden?

Tests were carried out on the usefulness of doubling the reference resistor during airways resistance measurement by forced oscillation method (set frequency technique). Measurements on 110 random subjects using the standard reference tube (Zo = 10 hPa/1/s) for comparison showed almost identical Ros values using the experimental tube, while the latter gave higher Ros values as obstruction increased. Comparisons with the bodyplethysmographic Rt on 65 patients with a chronic obstructive airways disease yielded a closer approximation to the identity curve from 7.0 hPa/1/s using this modified technique. The practical conclusion is to recommend the use of the double reference resistor for the basic clinical diagnosis of obstructive airways disease, both in quantifying advanced grade obstructions and in assessing the damaged respiratory mechanism in chronically ill patients with pronounced ventilatory resistance.

Evidence for bilateral vagal innervation of postganglionic parasympathetic neurons in chicken heart.

Stimulation of the cervical vagus nerves caused an output of acetylcholine (ACh) from the isolated chicken heart, which almost exclusively was released from the postganglionic neurons: (+)-tubocurarine (3 X 10(-14) M) reduced the output to 12 +/- 6% (n = 7) of the control. Stimulation of the two nerve trunks ws equally effective in releasing ACh.--Evidence that a large number of postganglionic neurons receives bilateral innervation was based on two experimental series. (1). The sum of the ACh outputs evoked by unilateral (separate) nerve stimulation of the right and the left vagus was higher than the bilaterally evoked output (100%) and increased with increasing frequencies (10, 20 and 40 Hz) from 115 +/- 13% to 131 +/- 9% (n = 13). In the presence of 10(-4) M 4-aminopyridine, unilaterally evoked output (40 Hz) was further increased from 131 to 176 +/- 5% (n = 21).--(2.) In the presence of 4-aminopyridine plus hemicholinium-3 (2 X 10(-5) M), unilateral nerve stimulation at 40 Hz evoked an output of ACh that decreased from 477 to 79 pmol g-1 min-1 during a 20 min-period of stimulation due to transmitter depletion. Thereafter output of ACh evoked by stimulation of the contralateral nerve was reduced by 73% as compared to the control value (475 pmol g-1 min-1; output without the preceding 20 min-stimulation).--It is concluded that a large number of parasympathetic postganglionic neurons of the chicken heart receives a dual excitatory input from both right and left vagus nerve.

Interstitial washout and hydrolysis of acetylcholine in the perfused heart.

The efflux of acetylcholine, of radioactively labelled acetylcholine and choline, into the venous effluent of the perfused chicken heart was studied to determine the kinetics of both interstitial washout and hydrolysis of acetylcholine. Stimulation of both cervical vagus nerves (e.g., for 5 s at 40 Hz) caused a release of acetylcholine, which appeared partially unhydrolyzed in the venous effluent, and reduced force of contraction and heart rate. For comparison, labelled acetylcholine or choline was infused for 5 s into the heart and again the venous efflux of either substance was determined. It was found that the kinetics of efflux of acetylcholine or choline from the interstitial space were of first order. The mean half times were 16.2 s (after infusion of acetylcholine) and 17.9 s (after nerve stimulation) for acetylcholine and 17.9 s (after infusion of choline) for choline. In the interstitial space, radioactivity (sum of [3H]-acetylcholine and [3H]-choline formed from [3H]-acetylcholine) released by nerve stimulation declined mono-exponentially with a rate constant of 0.069 s-1 and a half time of 10 s (due to washout), whereas the concentration of unhydrolyzed [3H]-acetylcholine decreased in multi-exponential fashion due to both washout and hydrolysis. The interstitial concentration of [3H]-acetylcholine reached the 50% level after 2.5 s. In conclusion, the long persistence of unhydrolyzed acetylcholine in the interstitial space of the heart appears to be due to an apparently low rate of hydrolysis. This, in turn, is responsible for the importance of diffusion and washout of acetylcholine from the interstitial space as significant factors of synaptic removal of acetylcholine. Moreover, the results support the notion that the sustained interstitial concentration of acetylcholine determines the long duration of cardiac responses to vagal stimulation.

[Basic-diagnostic-criterions of respiratory insufficiency--results of a community work of the working group "pathophysiology of breathing" (author's transl)]. / Basisdiagnostische Kriterien der respiratorischen Insuffizienz--Ergebnisse einer Gemeinschaftsarbeit der Arbeitsgruppe "Pathophysiologie der Atmung"

11 laboratories of the working group "Pathophysiology of Breathing" cooperated with standardized methods to obtain generally admitted practical criterions for the definition of respiratory insufficiency. Function parameters of 2800 examined persons in different diagnostic groups were tested by manual statistical analysis and computed by data processing system. which were assessed with regard to their usefulness as criterions for respiratory insufficiency. The arterial O2-partial pressure proved to be the most crucial criterion of respiratory insufficiency permitting objective evidence of a manifest respiratory insufficiency by hypoxeamia under standard efforts with a bicycle-ergometer. The screening parameters of ventilation such as vital capacity and forced exspiratory volume are suitable as subjective rapid methods for a quantitative estimation of one type of respiratory insufficiency: the ventilation disturbance. Investigations, which were carried out with a higher apparatus expense like the estimation of residual volume, the functional residual capacity, and the arterial CO2-partial pressure permit the further differentiation of causes of the respiratory insufficiency and the separation between respiratory partial- and global insufficiency. The parameters of gas exchange: O2-consumption, respiratory quotient, and the screening parameter of cardiocirculation heart rate are not or only limited useful as criterions of respiratory insufficiency alone.