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Principles of Good Practice for the Translation and Cultural Adaptation Process for Patient-Reported Outcomes (PRO) Measures: report of the ISPOR Task Force for Translation and Cultural Adaptation.

In 1999, ISPOR formed the Quality of Life Special Interest group (QoL-SIG)--Translation and Cultural Adaptation group (TCA group) to stimulate discussion on and create guidelines and standards for the translation and cultural adaptation of patient-reported outcome (PRO) measures. After identifying a general lack of consistency in current methods and published guidelines, the TCA group saw a need to develop a holistic perspective that synthesized the full spectrum of published methods. This process resulted in the development of Translation and Cultural Adaptation of Patient Reported Outcomes Measures--Principles of Good Practice (PGP), a report on current methods, and an appraisal of their strengths and weaknesses. The TCA Group undertook a review of evidence from current practice, a review of the literature and existing guidelines, and consideration of the issues facing the pharmaceutical industry, regulators, and the broader outcomes research community. Each approach to translation and cultural adaptation was considered systematically in terms of rationale, components, key actors, and the potential benefits and risks associated with each approach and step. The results of this review were subjected to discussion and challenge within the TCA group, as well as consultation with the outcomes research community at large. Through this review, a consensus emerged on a broad approach, along with a detailed critique of the strengths and weaknesses of the differing methodologies. The results of this review are set out as "Translation and Cultural Adaptation of Patient Reported Outcomes Measures--Principles of Good Practice" and are reported in this document.

Advisory Committees↗
PubMed1993

Mechanism of baroreceptor adaptation in dogs: attenuation of adaptation by the K+ channel blocker 4-aminopyridine.

1. Increased arterial pressure increases baroreceptor activity but activity declines (i.e. baroreceptors adapt) as the pressure is maintained at the higher level. The purpose of this study was to investigate the role of a 4-aminopyridine (4-AP)-sensitive K+ current in causing baroreceptor adaptation. 2. Multi- and single fibre recordings of baroreceptor activity were obtained from the vascularly isolated carotid sinus in anaesthetized dogs during step increases in carotid sinus pressure sustained for periods up to 5 min. 3. Baroreceptor activity increased with the rise in pressure, declined markedly over the first minute, and continued to decline at a slower rate during the remainder of the 5 min period of elevated pressure. Exposure of the isolated carotid sinus to 4-AP (10(-5) and 10(-4) M) attenuated adaptation in a dose-dependent and reversible manner (P < 0.05). 4-AP attenuated the gradual decline in single fibre activity and also prevented derecruitment or dropout of fibres that occurred over time. 4-AP did not alter peak nerve activity measured within the first 2 s of the pressure step. 4. Ouabain (5 x 10(-7)-10(-6) M), an inhibitor of Na+,K(+)-ATPase, increased baroreceptor activity but did not attenuate baroreceptor adaptation. 5. Neither 4-AP nor ouabain altered the distensibility of the carotid sinus as measured with sonomicrometer crystals suggesting that the agents act directly on the nerve endings. 6. The results suggest that activation of a 4-AP-sensitive K+ current contributes significantly to baroreceptor adaptation with little or no contribution of Na+,K(+)-ATPase.

4-Aminopyridine↗
PubMed2002

Invited review: molecular adaptations in mammalian hibernators: unique adaptations or generalized responses?

Hibernators are unique among mammals in their ability to attain, withstand, and reverse low body temperatures. Hibernators repeatedly cycle between body temperatures near zero during torpor and 37 degrees C during euthermy. How do these mammals maintain cardiac function, cell integrity, blood fluidity, and energetic balance during their prolonged periods at low body temperature and avoid damage when they rewarm? Hibernation is often considered an example of a unique adaptation for low-temperature function in mammals. Although such adaptation is apparent at the level of whole animal physiology, it is surprisingly difficult to demonstrate clear examples of adaptations at the cellular and biochemical levels that improve function in the cold and are unique to hibernators. Instead of adaptation for improved function in the cold, the key molecular adaptations of hibernation may be to exploit the cold to depress most aspects of biochemical function and then rewarm without damage to restore optimal function of all systems. These capabilities are likely due to novel regulation of biochemical pathways shared by all mammals, including humans.

Adaptation, Physiological↗
PubMed2004

Deadaption and readaptation with lactose, but no cross-adaptation to lactulose: a case of occult colonic bacterial adaptation.

The standard 3 h breath hydrogen (3hBH2) test distinguishes lactose maldigesters from lactose digesters. However, multiple factors impact on BH2 and care is needed to exclude a priori variables. When these factors are controlled, a negative BH2 test implies lactase persistent status or lactase nonpersistent status with colonic adaptation. A case of a Sicilian man who tested negative (lactase persistent status confirmed) on an initial 50 g lactose challenge is described. It was observed that he consumed 28.1 g lactose/day before testing. He subsequently underwent five additional challenge tests in the course of the next 10 months. In four tests the dose intake of lactose was varied upon instruction, and in the fifth test a 30 g lactulose challenge was carried out. It was demonstrated that on radically decreasing lactose intake, a full lactase nonpersistent status was unmasked. Output of 3hBH2 varied inversely with daily lactose intake. Finally, at a time when he was readapted to lactose, there was no discernible adaptation to lactulose challenge. It was concluded that 'occult' colonically adapted subjects may contribute to negative BH2 tests. There is a relationship between variation in lactose intake and the results of BH2 testing. Finally, there was no cross-adaptation to lactulose challenge when lactose was used as the adapting sugar.

Adaptation, Physiological↗
PubMed1977

Specific and general contour adaptation effects found using a selective adaptation paradigm.

There is evidence for discrete property analyzers in mammalian visual systems. Research has indicated that prolonged stimulation of such units reduces their sensitivity to subsequent stimulation. Psychophysical studies have employed this effect, terned selective adaptation, to study feature extractors in the human visual system. The purpose of this study was to determine the role of density and deviation in the adaptation figure on the recognition thresholds of simple and complex text figures. A selective adaptation paradigm was employed. A strict property analyzer model suggests that increases in density, deviation, or complexity should lead to an increased recognition time for the test figures. This was not confirmed. The complexity of the test figure had no effect on its recognition time. Both increased density and deviation did have an effect on the recognition times of the test figures. The results thus suggest that contour adaptation involves at least two processes: a general, probably peripheral effect due to the fatigue of visual receptor units and a more specific effect generated by the similarity between test figure and adaptation contours, independent of the site of stimulation.

Adaptation, Ocular↗
PubMed2000

Adaptations made by rheumatoid arthritis patients to continue working: a pilot study of workplace challenges and successful adaptations.

OBJECTIVES: The goals of this pilot study were to use qualitative research techniques in a group of currently employed patients with rheumatoid arthritis (RA) to develop categories of challenges encountered in maintaining employment and categories of successful adaptations made to continue working; and to identify obstacles considered to be persistent threats to continued employment. METHODS: Patients were interviewed by telephone with a questionnaire composed of structured-response format and open-ended response format questions focusing on specific challenges and adaptations in the workplace. RESULTS: Of the 22 patients interviewed, 96% were women, mean age was 50 years, 84% were college graduates, and the majority had light physical job demands and high autonomy over their work and hours worked. Patients encountered diverse challenges, such as fatigue, pain, typing, writing, physical requirements, maintaining a pleasant disposition, working overtime, traveling for business, commuting, being on time, not being able to choose rest periods, and environmental issues. Patients also made multiple adaptations to continue working, the most helpful being changing job or altering career path (36%), altering work hours (32%), using more disease-modifying antirheumatic drugs (27%), using car service (23%), sleeping more (18%), and working at home (14%). Patients were not at all confident in their ability to continue working because of RA, and perceived the following persistent threats to continued employment: fatigue (45%), not being able to use hands (45%), not being able to choose rest periods (27%), and commuting problems (18%). In addition, patients confronted psychological stresses, such as dealing with coworkers and supervisors and balancing job and personal roles. These challenges and adaptations included unfavorable work-related occurrences, or "negative work-role events." CONCLUSIONS: Seemingly successfully employed patients with RA faced multiple challenges and made major adaptations to maintain employment and still perceived their employment to be in jeopardy because of RA. The findings of this study have important implications for screening patients at risk for negative work-role events and for possible work-related and social support interventions aimed at preserving employment.

Activities of Daily Living↗
PubMed1979

[Dynamic behavior of the adaptive control system, hypothalamus--anterior pituitary--adrenal cortex. Animal experimental study of the adequate system dynamics of the direct and indirect parameters of the adaptive control system].

The dynamic response of the adaptive closed-loop control system hypothalamus-anterior pituitary-adrenal cortex after application of short-time disturb pulses were examined experimentally in the pig. Blood sampling was performed biologically non-reactive by chronically implanted vascular catheters in the upper vena cava. A circadian biphase periodical dynamics characterizes the distrubance response of the adaptive control system, respectively, its direct and indirect parameters. After distrubance variables induced initial excess the plasma corticosteriods undershoot the basic level over a long period. Conversely, the dynamics of the eosinophils is determined through an initial eosinopenic phase and a subsequent typical overshoot. Periodical dynamic is absent in the steady state. The controller of the adaptive system does not show any spontaneous activity in the steady state without stress. The absence of an endogenic periodicity of the dependent parameters likewise gives evidence of an active oscillator. On the other hand, the controlling unit of the adaptive system constitutes a control response of circadian periodicty after activation by disturbance variables in pulse shape. The high damping of the control system terminates the transient state within 24 hours, and the corticosteriods and the eosinophils reach the steady state level. This control quality of the adaptive control system gains a high importance in the origination of the spontaneous circadian periodicity by corticosteriods and eosinophils and for the biological compensation of exogenous distrubance variables.

11-Hydroxycorticosteroids↗
PubMed1989

[Study on choroidal blood flow at dark and light adaptation. 1. Choroidal blood flow at dark adaptation].

The effect of dark adaptation on choroidal blood flow (CBF) was studied in albino rabbits. CBF was measured by the hydrogen clearance method. There was no significant change of CBF at dark adaptation in both short term dark adaptation, in which CBF had been expected to increase due to increased oxygen demand of the outer retina, and long term dark adaptation, in which CBF had been expected to decrease due to depressed function of visual cells and retinal pigment epithelium. The results show that dark adaptation does not influence CBF, in spite of the close relationship between the outer retina and the choroidal circulation. The large blood flow of the choroidal circulation may not need the reaction mechanism for the functional changes of the outer retina.

Animals↗
PubMed1994

[Adaptive and non-adaptive reactions of vision in the Far North].

The paper deals with the study of specific features of ocular adaptive reactions under the conditions of the Far North. The author suggests that there should be 3 types of ocular adaptation in the North: (1) and (2) being at the individual level and (3) at the population level. Type 1 adaptation is usually observed within the first months of stay in the North. The ocular status of newcomers is characterized by lower hydrodynamic parameters: a tendency to intraocular vascular dystonia (the hypertensive type) is formed. Type 2 adaptation is generally seen after spending 10 years of stay in the North. Persistent physiological vascular reactions are formed (within the upper normal range). Organic disadaptive changes in microvasculature develop in a third of the new residents in the North. Type 3 hereditary long-term adaptation is observed in the indigenous residents of the North. The most optimum ratios of hemo- and hydrodynamic parameters along with definite changes in anatomic and functional indices form in them, which is reflected in the specific features of eye diseases.

Adaptation, Ocular↗
PubMed2003

A complex-valued nonlinear neural adaptive filter with a gradient adaptive amplitude of the activation function.

A complex-valued nonlinear gradient descent (CNGD) learning algorithm for a simple finite impulse response (FIR) nonlinear neural adaptive filter with an adaptive amplitude of the complex activation function is proposed. This way the amplitude of the complex-valued analytic nonlinear activation function of a neuron in the learning algorithm is made gradient adaptive to give the complex-valued adaptive amplitude nonlinear gradient descent (CAANGD). Such an algorithm is beneficial when dealing with signals that have rich dynamical behavior. Simulations on the prediction of complex-valued coloured and nonlinear input signals show the gradient adaptive amplitude, CAANGD, outperforming the standard CNGD algorithm.

Algorithms↗
PubMed1993

A comparison of self-adaptation and cross-adaptation to odorants presented singly and in mixtures.

Fifteen subjects made 450 judgments each by the method of magnitude estimation of dimethyl disulfide and hydrogen sulfide after prior exposure to various mixtures of them. Exposure to the same odorant clearly affected the perceived intensity of it (self-adaptation). By contrast, exposure to the other odorant showed at best a small effect (cross-adaptation). Consistent with this, adaptation to a mixture of the test odorant and another odorant is proportional to the amount of the test odorant in the mixture, and does not exceed that of self-adaptation. These results indicate that olfactory adaptation is specific and that the sense of smell is more robust than generally assumed.

Adult↗
PubMed1996

Adaptation to repeated restraint stress in rats: failure of ethanol-treated rats to adapt in the stress schedule.

Adaptation to a repeated restraint stress schedule was monitored in ethanol-treated and control rats. A single episode of 2 h restraint decreased food intake in both control and ethanol-treated rats. The decreases in control rats were not observed following the 5th daily restraint of 2 h/day, suggesting that adaptation has occurred. Ethanol-treated rats, however, exhibited decreased food intake even after 5th daily restraint of 2 h/day. Ethanol administration decreased weekly but not daily cumulative food intake in unrestrained rats. Food intakes of ethanol-treated and control restrained rats were comparable following 1st-3rd daily restraints, but were smaller in ethanol-treated rats following the 4th and 5th daily restraints. Open-field ambulatory activities monitored 24 h after the 5th daily restraint on the 6th day were comparable in control restrained and unrestrained rats. Ethanol-treated and control unrestrained rats also exhibited comparable ambulation, but ethanol-treated rats exhibited smaller activity than control restrained or ethanol-treated unrestrained rats. Fluid intakes of ethanol and control rats were comparable during the 2 weeks of ethanol administration, but daily restraint schedule decreased ethanol intake. The findings show adaptation to repeated restraint in control rats and inability of ethanol-treated rats to adapt in the stress schedule. These findings imply that excessive alcohol consumption may impair adaptation to stress and thus conceivably precipitate depression.

Alcoholism↗
PubMed2001

Evolution of adaptive synapses: robots with fast adaptive behavior in new environments.

This paper is concerned with adaptation capabilities of evolved neural controllers. We propose to evolve mechanisms for parameter self-organization instead of evolving the parameters themselves. The method consists of encoding a set of local adaptation rules that synapses follow while the robot freely moves in the environment. In the experiments presented here, the performance of the robot is measured in environments that are different in significant ways from those used during evolution. The results show that evolutionary adaptive controllers solve the task much faster and better than evolutionary standard fixed-weight controllers, that the method scales up well to large architectures, and that evolutionary adaptive controllers can adapt to environmental changes that involve new sensory characteristics (including transfer from simulation to reality and across different robotic platforms) and new spatial relationships.

Computer Simulation↗
PubMed1978

[Na-K ionic pump and spike adaptation in the slowly and rapidly adapting stretch receptor neuron of the crayfish Orconectes limosus (RAF.)].

A very important cause of the spike adaptation in the slowly adapting stretch receptor neuron (SN1) is the Na-K ionic pump. An increasing inhibition of the ionic pump, produced by gradual reduction of the external K+-concentration or application of rising doses of ouabain, is correlated with an adequate diminution of frequency decay. But even high concentrations of ouabain (10(-3) -- 5 . 10(-3) M) can not completely abolish the spike adaptation. Immediately after the onset of a current step the impulse frequency still declines. In agreement with these findings the gain in the Bode diagram shows a maximum further on. The spike adaptation in the rapidly adapting neuron (SN2) can only in a smaller part be attributed to the action of the ionic pump. Application of ouabain causes in the SN2, contrary to SN1, only a low depolarization of the membrane potential. The decay of impulse frequency is considerably diminished but a long lasting nearly stationary discharge like in the SN1 can never be observed.

Animals↗
PubMed1997

Evolutionary psychology and genetic variation: non-adaptive, fitness-related and adaptive.

Behavioural variation across individuals can be substantial. A broad generalization emerging from three decades of behavioural genetic studies is that most psychological individual differences have moderate broad heritabilities (30-60%). There are at least three possible scenarios for this genetic variation. First, it may be adaptively neutral and not subject to selection. Second, it may be related to fitness despite selection. Third, it may be maintained by selection for alternative adaptations. Some authors favour the first of these possibilities, but the latter two cannot be ruled out. First, temporally varying selection pressures (e.g. pathogens) can maintain fitness-related genetic variance in a population despite current selection pressures. Moreover, direct and indirect evidence on humans support the notion that some phenotypic variance is fitness related. Second, while adaptive alternatives are unlikely to be found at a level of highly complex design, frequency dependent selection can maintain variation at finer, quantitative levels. One potential example is discussed. Because of their particular relevance to evolutionary psychology, fitness-related and adaptive genetic variance deserve further attention.

Adaptation, Psychological↗
PubMed1987

Two types of chloride cells in the gill epithelium of a freshwater-adapted euryhaline fish: Lebistes reticulatus; their modifications during adaptation to saltwater.

Two types of chloride cells were identified in the gill epithelium of freshwater-adapted guppies. One type, referred to as an "alpha-chloride cell," was a pale, elongated cell located at the base of the secondary lamella in close contact with the arterioarterial pillar capillaries. In its cytoplasm, membranous tubules in continuity with its basolateral plasma membrane formed an extended tridimensional network. The vesiculotubular system (Pisam: Anat. Rec. 200:401-414, 1981) consisted of a few tubules and vesicles located next to the apical plasma membrane. A second type, referred to as a "beta-chloride cell," was a darker, ovoid cell located in the interlamellar region of the primary epithelium facing the central venous sinus. Membranous tubules in continuity with the basolateral plasma membrane were unevenly distributed in the cytoplasm. A prominent vesiculotubular system composed of numerous vesicles and tubules was found between the Golgi apparatus and the apical surface. During seawater adaptation, the alpha-chloride cells increased in size and progressively transformed into characteristic "seawater alpha-chloride cells" with a well-developed, regular, tight tubular network and numerous vesicles and tubules of the vesiculotubular system accumulated below the apical pit. The beta-chloride cells underwent a progressive degeneration and disappeared. Thus, in freshwater-adapted guppies, there are two types of chloride cells, alpha and beta, respectively, related to the arterial and the venous vessels, whereas in seawater-adapted fishes, a single type of cell, the alpha-chloride cell, was related to both the arterial and venous channels.

Adaptation, Physiological↗
PubMed1987

Dependence of cat vestibulo-ocular reflex direction adaptation on animal orientation during adaptation and rotation in darkness.

Four series of experiments investigated how adaptive changes in direction of the cat's vestibulo-ocular reflex (VOR) vary with position of the animal during adaptive training and postadaptive testing. In all experiments VOR was measured electrooculographically during rotations about earth-horizontal and vertical axes in the dark before and after 2 h of adaptation in which 0.25 Hz sinusoidal whole body rotation about a horizontal/vertical axis was paired with synchronous 0.25 Hz rotation of a visual pattern about a vertical/horizontal axis, respectively. In upright sagittal (US) experiments, coupling of pitch rotation with visual pattern rotation about an earth vertical axis yielded an adaptive horizontal VOR response to pitch rotation whose gain had a local maximum at 0.25-0.5 Hz plus a sustained rise for frequencies below 0.1 Hz. When post-tests were done with the animal rolled 90 degrees onto its side and rotated about the earth vertical axis (pitch relative to the cat), the low frequency rise was eliminated and the 0.25 Hz peak was reduced. In on side sagittal (SS) experiments, where training was done in the latter (on side) position, training produced only the 0.25 Hz peak without the low frequency rise, indicating that the rise is due to coupling of otolith input to horizontal VOR. Again the 0.25 Hz peak was reduced when testing was done with the cat oriented 90 degrees from the training position (in the US position). This indicates that the cross-coupled canal-ocular reflex response is modulated or gated by the position of the animal with respect to gravity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Ocular↗
PubMed1987

Effects of adaptation and cross-adaptation to common ions on sourness intensity.

The effects of self and cross-adaptation of acetic acid and HCl solutions on the perception of sourness, were investigated using a filter paper method. In contrast to acetic acid and to pH-buffered acetic acid solutions, self-adaptation could not be obtained with HCl. In fact the sourness of the HCl test-stimulus after adaptation to HCl was increased compared to the sourness obtained with the unadapted tongue. Such a sourness potentiation was also observed with acetic acid and buffered acetic acid solutions after adaptation to distilled water. The results suggest that the reception process eliciting the sour taste of H+ ions and of undissociated acids are different and probably independent.

Acetates↗