Biomedical subjects

T Kohlmann

Publications and source records attributed to T Kohlmann.

At least 19 recordsLinked to original sources

PubMed1999

The QoL-AGHDA: an instrument for the assessment of quality of life in adults with growth hormone deficiency.

Several studies have shown that growth hormone deficiency in adults leads to poor well-being and other clinical consequences, and that these improve when the hormone is replaced. However, the studies employed generic measures of health status that miss important aspects of the patients' experience and that have inadequate reliability and responsiveness. This paper describes the European development and testing of the Quality of Life-Assessment of Growth Hormone Deficiency in Adults (QoL-AGHDA), a condition-specific quality of life measure for use in clinical trials and for the routine monitoring of patients. The instrument was produced in five languages; English, Swedish, Italian, German and Spanish. Each language version is shown to have good reliability, internal consistency and construct validity. The QoL-AGHDA is currently included in an international database monitoring the long-term efficacy and safety of growth hormone replacement therapy and in clinical trials in a number of countries.

Adult↗

PubMed1999

[Health technology assessment in the international context: where does Germany stand? For the "German Scientific Working Group Technology Assessment for Health care"].

The evaluation of medical technologies, Health Technology Assessment (HTA), is gaining more and more importance in Germany. Starting from a comprehensive definition of the term medical technology, this article first describes the development of HTA since the seventies as an instrument for improving decision-making in health policy. HTA is presented as a repetitive cycle of a sequence of steps starting with the prioritization of topics to be evaluated to the analysis of the impact of the results. Current trends in the further improvement of HTA methods are described, such as the formalization of the topic selection. The current situation in Germany is presented with regard to the regulation of licensing/market entry, coverage by the statutory health insurance, and the utilization of medical technologies. Finally, current activities in the field of HTA in Germany as well as the role of the German Scientific Working Group Technology Assessment for Health Care are discussed.

Guidelines as Topic↗

PubMed1999

[Effectiveness of back-school programs in controlled trials. A review of the literature].

Backschools are utilized for primary, secondary and tertiary prevention of nonspecific low back pain while there is considerable doubt concerning their effectiveness. We present the results of controlled clinical trials that examine the effectiveness of back schools as reported in recent systematic reviews of the literature. An extensive literature search for systematic reviews summarizing the results of controlled trials was performed. Publications which satisfied a number of inclusion criteria concerning methodology and content were critically appraised. Their main results and conclusions are presented and discussed.

Controlled Clinical Trials as Topic↗

PubMed1998

Fetal hemoglobin in starvation ketosis of young women.

Ketones can reactivate the production of fetal hemoglobin (HbF) in vitro and in vivo. A reactivation of HbF by ketones, which are generated during starvation, remains largely speculative. Therefore, we investigated HbF in 31 women with anorexia nervosa or bulimia, using both of these as models of intermittent starvation ketosis. For comparison, we also studied 42 female control subjects matched for age. beta-Hydroxybutyrate levels were higher in patients than in controls (460 +/- 90 v 110 +/- 20 mumol/L; P < .0001). We correlated beta-hydroxybutyrate, metabolic, and hematologic parameters with HbF. HbF was measured with high pressure liquid chromatography. The data were analyzed with logistic regression analysis. An elevated HbF fraction (> 0.87%) was observed four times as often in patients than in controls (29% v 7%, P = .01). After adjustment for age, we found HbF elevations associated with beta-hydroxybutyrate levels (P = .005). No other correlations between the various metabolic/ hematologic parameters and HbF were significant. In conclusion, beta-hydroxybutyrate generated in starvation is associated with increased levels of HbF. Thus, unrestrained lipolysis can produce beta-hydroxybutyrate in sufficient quantities to induce a clinically measurable amount of HbF. These findings suggest that intermittent ketosis might also explain some increases of HbF in type 1 diabetes and pregnancy.

Adolescent↗

PubMed1998

The international development of the RGHQoL: a quality of life measure for recurrent genital herpes.

This paper describes the international development and psychometric testing of the Recurrent Genital Herpes Quality of Life Questionnaire (RGHQoL), a condition-specific quality of life (QoL) instrument. The theoretical foundation for the measure is the needs-based model of QoL and the content of the instrument was derived from in-depth qualitative interviews with relevant patients in the UK. Versions of the RGHQoL were required for the UK, USA, Italy, Germany, France and Denmark for use in international clinical trials. The results indicate that the final 20 item measure has good reliability, internal consistency and validity for all language versions. A small responsiveness study in Denmark suggested that the measure is sensitive to changes in QoL associated with the initiation of suppression treatment for recurrent genital herpes (RGH). It is concluded that the RGHQoL is a valuable instrument for inclusion in clinical trials. The psychometric properties of the instrument are such that it may also be used to monitor the progress of individual patients.

Adult↗

PubMed1998

[Measuring patient related outcome criteria in medical rehabilitation: how well do "indirect" and "direct" methods of measuring change agree?].

PURPOSE: To investigate agreement between "indirect" and "direct" methods for measuring outcome of inpatient rehabilitation programmes. METHOD: A consecutive sample of 610 patients with musculoskeletal, cardiopulmonary and other diseases completed questionnaires 2 weeks before and 4 to 6 weeks after inpatient rehabilitation treatment. Overall response rate was 80%. Patient outcome variables were measured at baseline and follow-up. These included 14 items covering general health, pain, functional limitations, sleep, energy, mood, and social contacts. In the follow-up questionnaire patients were also asked to recall their baseline situation and to answer the same items according to this recalled condition and, furthermore, to report directly the perceived change on a 3-point scale ("deteriorated", "unchanged", "improved"). Thus, three different methods for measuring change could be compared: changes observed prospectively between baseline and follow-up, change as the difference of recalled baseline status and observed follow-up status, and perceived change. RESULTS: Spearman correlation coefficients r(S) and Cohen' Kappa statistic were used to analyse association and chance-corrected agreement, respectively, between these three different methods. Correlation and agreement between the different indicators of change was only moderate to fair with r(S) varying between 0.10 and 0.65, Cohen's Kappa ranged between 0.07 and 0.62. Results of principal components analysis indicated that items representing perceived change did not reflect the substantive aspects of change and were assigned indiscriminately to one single component. CONCLUSION: Prospective and retrospective methods for measuring change are not functionally equivalent. Whenever feasible, prospective methods using observed baseline and follow-up data ("indirect" measurement of change) should be used in the evaluation of patient outcome in rehabilitation.

Activities of Daily Living↗

PubMed1998

[Rehabilitation-related expectations and motivations in patients with nonspecific backache. The development of a standardized questionnaire].

The success of rehabilitation programmes is assumed to be influenced by patients' expectations and motivations toward these regimens. Yet only few standardized measurement instruments of these patient attributes are available. This paper is concerned with the development of a standardized questionnaire measuring patients' expectations and motivations with respect to rehabilitation programmes. Basically derived from focus group discussions with chronically ill, we defined and operationalized four dimensions of expectations toward rehabilitation programmes. In applying the questionnaire it could be shown that the instrument is easy to use, shows acceptable psychometric properties and is correlated with relevant patient characteristics.

Activities of Daily Living↗

PubMed1997

The association between clinical findings on physical examination and self-reported severity in back pain. Results of a population-based study.

STUDY DESIGN: A cross-sectional population-based study of back pain. OBJECTIVE: To evaluate the association between clinical findings on physical examination and subjective severity in nonspecific back pain. SUMMARY OF BACKGROUND DATA: Assessment of severity of back pain always has been controversial. Most studies evaluating the role of clinical findings in back pain have been hospital- or clinic-based, often representing a highly select population. This selection is avoided in the population-based approach of the present study. METHODS: Approximately 4,000 German inhabitants of Lubeck, aged 25-74, were selected randomly from the local population registry and received a postal questionnaire. Those who reported "back pain today" (n = 1200) or "back pain within the past 12 months but no back pain before" (n = 75) were invited to come in for a clinical examination. Thirty-four physical measurements were taken. They were divided into four groups: static measurements, dynamic measurements, neurologic findings, and non-organic physical signs. Self-reported severity of back pain was measured by a pain questionnaire and a 12-item activities of daily living list to assess functional disability. RESULTS: Within each of the four groups of physical measurements, those that corresponded best with the subjective severity of back pain could be identified (e.g., rotation, lateral flexion, and fingertip-floor distance, scoliosis, the position of the side plumb line, and pain on percussion of the spine pseudo-Lasegue and hand muscle-strength). Those that corresponded best could be differentiated statistically from less correlative measurements such as kyphosis and lordosis; flexion of the lumbar, thoracic, or cervical spine, abdominal muscle strength, and axial loading. The agreement between the classification of back pain severity based on clinical findings and the classification based on self-reports was moderate (kappa = 0.47). CONCLUSIONS: Assessment of severity in back pain can only partly be based on the clinical findings of a physical examination. There is a relatively weak agreement between the results of physical examination and the subjective reporting of pain and disability.

Activities of Daily Living↗

PubMed1997

[German version of the Nottingham Health Profile (NHP): translation and psychometric validation].

The Nottingham Health Profile was developed in the late 70s in Great Britain and has since then been widely used in anglo-american countries as well as in other countries. We report about the translation process and the examination of psychometric properties of the German version of the Nottingham Health Profile in 10 samples of over 1000 healthy and ill persons. Results of psychometric assessment (feasibility, reliability, validity, sensitivity) were satisfactory. This suggests that the German translation of the Nottingham Health Profile is a reliable and valid instrument for patient-based reports of subjective health which can be used in clinical research as well as in epidemiologic studies.

Activities of Daily Living↗

PubMed1996

Latent class analysis in medical research.

In the introduction we give a brief characterization of the usual measures for indicating the quality of diagnostic procedures (sensitivity, specificity and predictive value) and we refer to their relationship to parameters of the latent class model. Different variants of latent class analysis (LCA) for dichotomous data are described in the following: the basic (unconstrained) model, models with parameters fixed to given values and with equality constraints on parameters, multigroup LCA including mixed-group validation, and linear logistic LCA including its relationship to the Rasch model and to the measurement of change in latent subgroups. The problem with the identifiability of latent class models and the possibilities for statistically testing their fit are outlined. The second part refers to latent class models for polytomous data. Special attention is paid to simple variants having fixed and/or equated parameters and to log-linear extension of LCA with its possibility for including on the latent level. Several examples are presented to illustrate typical applications of the model. The paper ends with some warnings that should be taken into consideration by potential users of LCA.

Clinical Trials as Topic↗

PubMed1996

Nocturnal blood pressure elevation is related to adrenomedullary hyperactivity, but not to hyperinsulinemia, in nonobese normoalbuminuric type 1 diabetes.

We tested the hypothesis that insulin is an independent risk factor for elevated blood pressure. As our model we selected type 1 diabetes with peripheral circulatory hyperinsulinemia induced by sc insulin treatment. In 15 nonobese normoalbuminuric patients with type 1 diabetes (23.7 +/- 0.8 yr old) and in 15 healthy controls matched for age, sex, and body weight, ambulatory blood pressure was recorded over 24 h. The areas under the curve of free insulin (605 +/- 135 vs. 275 +/- 35 pmol/L.h; P = 0.03) and basal plasma epinephrine concentrations were higher (170 +/- 10 vs. 130 +/- 10 pmol/L; P = 0.02), and the basal aldosterone level was lower (220 +/- 40 vs. 410 +/- 50 pmol/L; P = 0.009) in the patients. The nocturnal decline in systolic blood pressure was less pronounced (13 +/- 1 vs. 19 +/- 2 mm Hg; P = 0.007) in the patients. Multivariate adjustment (r2 = 0.75; P = 0.0002) showed an effect of basal plasma epinephrine and norepinephrine levels and body mass index on the mean nocturnal systolic blood pressure, but showed no effect of age, sex, hemoglobin A1c, aldosterone, or, in particular, insulin. We found a blunted nocturnal fall in blood pressure in nonobese, normoalbuminuric type 1 diabetic patients. These patients showed increased adrenomedullary activity, and this predominantly contributed to the blood pressure alterations. We also found hyperinsulinemia in these patients, but, after controlling for covariates, blood pressure was independent of the insulin level.

Adolescent↗

PubMed1996

[A leukemia cluster in the Pinneberg district. Results of an incidence study by the epidemiologic task force of the Schleswig-Holstein Medical Association].

After regional media had reported in early 1995 of multiple leukaemia cases in a small community in the state of Schleswig-Holstein, an "Epidemiological Task Force" was asked to review the existing evidence for a possible cluster. The Task Force is a small group appointed in 1994 by the regional Medical Association and the state's ministry of social affairs. It includes five professionals from the fields of environmental toxicology and hygiene, Public Health, epidemiology and cancer pathology. In agreement with the local Public Health administration and the ministry the Task Force organized a retrospective screening of all incident leukaemia, lymphoma and myeloma cases (ICD-9 codes 200-208) within a (5-10 km) around the small community (population on December 31st 1993: 72000) that had occurred after January 1st 1990. Any practising physician (response rate 78%), hospital (100 %), oncological centre (100%), and tumour registry (100%) serving the region were asked to notify all relevant cases to the Task Force. Additionally spontaneous case reports were elicited, and all death certificates from the a.m. time period were screened for by two Public Health administrations. We identified 202 single cases for further analysis. Comparative data for the entire region and single communities came from two cancer registries, the Danish and that of the state of Saarland/FRG, and allowed for calculating the expected number of cases by indirect standardisation. While Hodgkin's lymphomas and myelomas were (insignificantly) less frequent than expected, an excess of non-Hodgkin's lymphomas and leukaemias (all types combined) was observed. Standardised incidence ratios for the whole region varied between 1.54 and 1.68 with significant and consistent increases only for the group of leukaemias among adults (aged 15+). All results were reported to both the public and administrative/professional bodies together with specific recommendations. The reactions showed a good acceptance of the Task Force and its work.

Adolescent↗

PubMed1996

[Hannover Functional Questionnaire in ambulatory diagnosis of functional disability caused by backache].

This paper describes conceptual and clinimetric aspects as well as fields of application of the Hannover Functional Ability Questionnaire for measuring back pain-related disability (FFbH-R). The FFbH-R belongs to a series of short self-administered questionnaires for the assessment of functional limitations in activities of daily living among patients with musculoskeletal disorders. In addition to the FFbH-R, a specific version is available for patients with polyarticular diseases (the FFbH-P), as well as a combined version of both questionnaires. A new questionnaire for patients with osteoarthritis is currently being developed. Data from various studies indicate that the FFbH-R meets the relevant psychometric criteria of acceptability, reliability, validity, and sensitivity to change. It has been successfully applied in (observational and controlled) clinical studies, in epidemiologic surveys, and in compensation disability evaluation.

Activities of Daily Living↗

PubMed1996

[Measuring functional capacity in backache patients in rehabilitation: a comparison of standardized questionnaires].

In recent years, subjective assessment of functional ability by patients has become an important diagnostic instrument in rehabilitation medicine. We compared three self-administered standardized questionnaires for measuring functional capacity in patients with back pain (the back pain-specific version of the Hannover Functional Ability Questionnaire, the Roland & Morris Scale, and the Measurement of Patient Outcome Scales) with respect to feasibility, reliability, and validity. The sample comprised 119 patients treated for back pain in a rehabilitation clinic in North Germany. Besides measures of functional ability, anamnestic and psychosociological data were collected in addition. Mobility of the spine was assessed by simple clinical tests. The three questionnaires differed only slightly with regard to their psychometric properties and appeared to be equally well suited for measuring functional ability in patients with back pain. The decision for one of the instruments should be based on practical considerations (time for completion, feasibility, availability of reference data).

Activities of Daily Living↗

PubMed1996

[Backache in East and West Germany].

On the basis of data of the East German Health Survey (1991/92) and regional studies from West Germany (Bad Säckingen 1990, Lübeck 1991/92, Bad Säkingen 1993/94) results on the prevalence of back pain, other rheumatic complaints and general health problems are compared. East German respondents report on back pain and all other rheumatic complaints definitely less often than West German respondents but suffer equally from general health complaints. Apart from the differences in the prevalence of rheumatic complaints there are remarkable structural analogies between East Germany and the West German cities. In any region, the back is the most often affected part of the body, followed by the neck, the shoulder, and the knee. Beyond that, there are similar age-related and sex-specific differences in prevalence rates of rheumatic complaints. In the groups of elderly people, a pattern of declining or constant prevalence rates can be noticed with many complaints. However, there are differences in pain intensity and functional limitations between East and West. The East German respondents particularly mention mild pain more rarely than respondents of the West German cities. They also report fewer functional limitations. This may indicate that in East Germany people attach less importance to rheumatic pain and deal with it in a different way. Possibly, the differences in prevalence can be explained thereby. To what extent they reflect real differences in morbidity cannot be clarified by the present data.

Activities of Daily Living↗

PubMed1994

Disorders characterised by pain: a methodological review of population surveys.

OBJECTIVE--To review a series of conceptual and methodological problems encountered in surveys primarily devoted to pain disorders. CRITERIA FOR INCLUSION AND EXCLUSION OF ARTICLES--Published reports were systematically collected by electronic database searches (Medline), citations in existing publications, and through personal contacts. Relevant articles from clinical and epidemiological research on pain were included and special attention was given to epidemiological research on back pain. CONCLUSIONS--Surveys of pain disorders should be based on a multidimensional pain model that includes nociceptive input, pain perception, suffering, and pain behaviour as major components. Because of the limited applicability of diagnostic procedures or genuine "non-specificity" of pain states, or both, epidemiological surveys may result in a considerable proportion of cases without an identifiable pathophysiological basis. Staging and grading procedures for pain disorders (as distinguished from classification) may comprise various aspects of pain perception: regional distribution, pain intensity, temporal characteristics, sensory qualities, and dimensions of cognitive-emotional appraisal. Description of temporal development and chronification (staging) should refer to different components of the multidimensional pain model. Explicit a posteriori procedures for grading are preferable to implicit grading based on question wording. Evidence from several sources suggests that localistic concepts of pain may be misleading. Identification of complex pain syndromes should be one primary target for epidemiological pain surveys. Of the many factors that may impair the reliability and validity of data collected in pain surveys, recall biases seem to deserve special attention.

Back Pain↗

PubMed1994

[The current backache epidemic].

All available data presented show that we are confronted with a back-pain (BP) epidemic; it affects numerous industrialized countries. More severe forms of BP make up one fifth of the prevalence. The greater part of BP seems to be mild, especially among persons aged 25 to 54. The social insurance statistics, too, show an alarming trend. Cases of work incapacity and medical rehabilitation have increased drastically: one sixth of all cases of work incapacity as well as one third of all medical rehabilitations are to be accounted to BP. It is not easy to interpret the data. Do they represent an increasing BP epidemic? A long-term secular trend towards higher BP prevalences at the population level is to be assumed but cannot be proven at the moment. Is there any evidence that BP-related risk factors have increased? To our knowledge there are no reliable data. It is also to be considered that the 'natural' course of BP may have changed. Is the epidemic a consequence of an increasing 'chronification' of BP due to physical, psychosocial or medical influences? Do 'back-schools' and other factors regarding the BP business have only health-promoting effects? Does the date represent a changing perception and appraisal of pain and/or a changing 'pain-reporting behaviour'? Is 'pain' today what would have been 'discomfort' in former times? Does one complain about BP today when one would have been silent in former times? There are no valid data for these hypotheses, either. Finally, has the transition probability from pain to disability and to social benefits changed?(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

[Grading of backache].

Back pain is occurring in a broad spectrum of severity; therefore, a grading procedure which is derived from a sound conceptual basis and can be easily applied is of crucial importance in clinical research and in epidemiologic studies. Following a grading procedure which has been developed in epidemiologic studies in the U.S., a hierarchical model for grading is proposed. This comprises pain intensity and functional limitation as basic criteria as well as aspects of time, pain-related cognitions/emotions and concomitant complaints. An application of a simple grading procedure is used to illustrate the predictive utility of the proposed model.

Activities of Daily Living↗