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Results for “Observation”

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PubMed1995

Inter-observer variability in the assessment of nerve function in leprosy patients in Ethiopia.

One of the major problems in leprosy is to detect any change in nerve function early enough so as to increase the chances of recovery and prevent disability. Several tests have been developed to assess nerve function and are used in leprosy control programs worldwide, but they are frequently performed by different workers on different occasions and under variable conditions. In this study we investigated the variability between different groups of observers in the assessment of nerve function in leprosy patients in Ethiopia. Sensory function was assessed by using a set of nylon monofilaments (NF) and a ball-point pen (BP), and motor function was assessed by using voluntary motor testing (VMT). We also studied the variability between observers in the assessment of the clinical signs of neuritis. Duplicate measurements were performed in random order on 50 leprosy patients by two physio-technicians and on 50 other patients by two health assistants. The percent agreement between observers was calculated for each single nerve, and weighted kappa statistics were used to assess whether agreement was better than expected due to chance alone. Systematic differences between observers were evaluated using the Wilcoxon signed rank test. On sensory testing, inter-observer variability was found to be related to the training and experience of the observer, to the nerve tested, and to the neurological status of the patient. When tests were performed by physio-technicians, we observed 32% to 58% agreement with the NF test and 71% to 84% agreement with the BP test, measured on different scales. After weighting for the scale difference, the agreement seemed comparable with these methods but the differences in measurements with the BP test were found to be dependent upon the neurological status of the patient. The variability between observers differed according to the nerve tested, and there was some evidence of systematic differences between observers with both methods. When performed by the health assistants, agreement was between 34% and 46% with the NF and between 66% and 82% with the BP tests. After weighting for the scale difference, the agreement seemed comparable but the BP was not liable to the systematic differences seen in the NF results. These differences could be attributed to the differences in the experience of the workers with these tests. With the VMT, small variability between observers was found for all nerves tested, except the facial nerve, when performed by both the physio-technicians and by the health assistants (72% to 98% agreement).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1998

Observation learning in day-old chicks using a one-trial passive avoidance learning paradigm.

We tested the hypothesis that day-old chicks, Gallus gallus domesticus, can learn to avoid an aversive stimulus if they observe the responses of another chick. In experiment 1, one of a pair of chicks (the actor) was allowed to peck at a bead coated in the bitter-tasting substance methylanthranilate (MeA), while we prevented the other chick (the observer) from pecking the bitter-tasting bead by separating the chicks with a piece of wire mesh. Both chicks avoided pecking at a similar but dry bead 0.5, 3 and 24 h after the observer chick saw the actor chick peck at an MeA-coated bead. By contrast, when the actor chick had pecked at a water-coated bead, both chicks continued to peck at a dry bead at 0.5, 3 and 24 h after training. Experiment 2 investigated whether observer chicks showed avoidance if they were prevented (by the insertion of an opaque barrier) from observing their companion pecking at the MeA-coated bead during either training or testing. Observer chicks that could not see their companion during training but could observe the actor chicks at test showed no subsequent avoidance whereas chicks that observed the actor chick at training, but not during testing, showed high levels of avoidance. Although the sensory cues (visual, auditory or olfactory) or types of behaviour (i.e. levels of pecking or head shaking) that the observer chick used to maintain avoidance remain unclear, the results show that chicks can learn about an aversive object by observing the responses of a conspecific. (c) 1998 The Association for the Study of Animal Behaviour.

Journal Article↗

PubMed2002

Lateralization in motor facilitation during action observation: a TMS study.

Action observation facilitates corticospinal excitability. This is presumably due to a premotor neural system that is active when we perform actions and when we observe actions performed by others. It has been speculated that this neural system is a precursor of neural systems subserving language. If this theory is true, we may expect hemispheric differences in the motor facilitation produced by action observation, with the language-dominant left hemisphere showing stronger facilitation than the right hemisphere. Furthermore, it has been suggested that body parts are recognized via cortical regions controlling sensory and motor processing associated with that body part. If this is true, then corticospinal facilitation during action observation should be modulated by the laterality of the observed body part. The present study addressed these two issues using TMS for each motor cortex separately as participants observed actions being performed by a left hand, a right hand, or a control stimulus on the computer screen. We found no overall difference between the right and left hemisphere for motor-evoked potential (MEP) size during action observation. However, when TMS was applied to the left motor cortex, MEPs were larger while observing right hand actions. Likewise, when TMS was applied to the right motor cortex, MEPs were larger while observing left hand actions. Our data do not suggest left hemisphere superiority in the facilitating effects of action observation on the motor system. However, they do support the notion of a sensory-motor loop according to which sensory stimulus properties (for example, the image of a left hand or a right hand) directly affect motor cortex activity, even when no motor output is required. The pattern of this effect is congruent with the pattern of motor representation in each hemisphere.

Adult↗

PubMed1992

Working postures and activities of lorry drivers: a reliability study of on-site observation and recording on a pocket computer.

Poor working postures are associated with the development of musculoskeletal disorders. Many different observation methods have been developed to analyse working posture and activity. TRAC (Task Recording and Analysis on Computer) enables the observer to choose and define the variables and the categories within variables to be recorded at the workplace and analysed afterwards. In this study, inter-observer reliabilities were determined for the variables that were essential to ensure accurate recording of both working posture and activity of lorry drivers. The pre-set standard for observer reliability was not reached before the number of variables was decreased: the variables concerning activities and load handled were omitted in favour of those concerning body posture. As a result of this reliability study an improved application of TRAC is proposed. For the purpose of recording all selected variables a second observer is introduced, so that two observers work simultaneously at the working site. The first observer pays attention only to working postures and the second observer records, among other things, activities. An additional program has been written to combine the variables of both observers for subsequent analysis. This enables us to investigate the relation between activity, appliances or goods being handled, and the corresponding working postures. The second observer records on a real-time basis and provides accurate information on the duration and sequence of activities. It is considered that this twofold application of TRAC is an important contribution to the accurate analysis of workplaces.

Journal Article↗

PubMed1996

Reactivity and repeatability of hygiene behaviour: structured observations from Burkina Faso.

If interventions promoting improved hygiene behaviour to prevent childhood diarrhoea are to be implemented and evaluated, valid methods for measuring this behaviour will be required. This paper presents findings from a study to investigate the use of structured observations to measure hygiene behaviour in Burkina Faso. Two hundred mothers with young children (2-36 months) were observed on several occasions, with particular attention focused on events/behaviour surrounding defaecation. Child defaecation occurred most often in a potty (67% of occasions). Stools were most often disposed of into a latrine (79%). Following defaecation the child's bottom was usually rinsed using water alone with a bare hand (76%). Subsequent hand washing by the mother/caretaker was much rarer (29%). None of these behaviours appeared "reactive" to the presence of the observer. Less common behaviors showed some evidence of reactivity. The frequency of child defaecation in the yard increased over the course of three observations (5% to 16%; P = 0.01) and the proportion of occasions on which the child was observed to be cleaned after defaecation declined (95% to 85%; P = 0.01). Mothers usually took with them to the latrine a water recipient (91%). Hand washing after leaving the latrine was observed on 30% of occasions. This proportion declined from 36% to 22% over three observations (P = 0.05). Defaecation by older siblings (aged 3-5 years) was usually into a potty (48%) or directly in a latrine (30%). There was no evidence that this behaviour was reactive. The repeatability of behaviours at the individual level was generally low. The site of index child defaecation (kappa = 0.27), how the child's bottom was cleaned (kappa = -0.01) and whether the caretaker washed her hands afterwards (kappa = 0.26) all showed low repeatability. The method of stool disposal was more repeatable (kappa = 0.73). Hand washing by mothers after using the latrine showed moderate repeatability (kappa = 0.40). Older sibling's defaecation behavior had excellent repeatability (kappa = 0.90). Our findings suggest that, in studies which aim to measure behaviour at the population level, structured observations may provide a useful tool. Studies which investigate links between hygiene behaviour and diarrhoea incidence at the individual level will require repeated observations of mothers and children since measuring behaviour during a single observation will lead to misclassification of exposure status, resulting in bias which could mask any underlying association. This is likely to be very costly.

Adult↗

PubMed2004

Volumetric model and human observer comparisons of tumor detection for whole-body positron emission tomography.

RATIONALE AND OBJECTIVES: The performances of model and human observers were compared for detecting and localizing tumors in whole-body positron emission tomography imaging. Volumetric implementations of model observers were used instead of standard planar implementations to reproduce the common practice of using volumetric image displays to assess whole-body positron emission tomography images. MATERIALS AND METHODS: Observer studies with simulated data were used to compare three different acquisition protocols for an average patient size. Multiple realizations of simulated whole-body data with multiple added 1-cm diameter spherical lesions (targets) per image volume for efficiency were used. The location and contrast ratio of the targets were chosen randomly within ranges determined by initial calibration studies. Human observer studies were performed using a volumetric image display routinely used in clinical practice, and human observer detection performance was quantified using an alternate free-response operating characteristic analysis. The human detection performances were compared with the performances of volumetric implementations of the non-prewhitening matched filter and the channelized hotelling observer and also to the target contrast measured in the reconstructed image. RESULTS: Human observer detectability was generally well described as a linear function of these three figures of merit for the detection task considered. The best correlations (r = 0.96, rho = 0.98) were achieved with the channelized hotelling observer and non-prewhitening matched filter model observers. CONCLUSION: The use of volumetric model observers provides a means for quantitative comparisons of different protocols and also provides a useful tool for the optimization of key parameters in whole-body positron emission tomography imaging.

Humans↗

PubMed2004

Differential modulation of corticospinal excitability during observation, mental imagery and imitation of hand actions.

In this study, we attempted to better delineate the changes in corticospinal excitability that accompany perceptual to motor transformations when people are asked to observe, image or imitate actions. Motor evoked potentials (MEP) from transcranial magnetic stimulation were recorded in the first dorsal interosseous (FDI) muscle of the dominant hand (15 right, 4 left) in five different conditions: (1) passive observation; (2) observation to imitate; (3) imagery; (4) imitation; and (5) counting backwards mentally. MEPs were also recorded at rest at the beginning and at the end of the session to establish baseline (BL) values. For the observation conditions, participants (n=19, 18-38 years) watched video sequences (5s) of hand actions performed by a model with the right arm (passive observation: scissors; observation to imitate: OK sign). Active imitation produced the greatest MEP facilitation compared to baseline, followed by the two observation conditions and the imagery conditions, which all produced similar levels of facilitation (post hoc comparisons). Mental counting produced some facilitation, but this effect was inconsistent. Baseline MEPs remained stable at the end of the session. A further comparison between right-handers (n=15) and left-handers (n=4) revealed no difference in the pattern of modulation across conditions. The similarity found between observation and imagery of hand actions in terms of corticospinal facilitation is interpreted in the light of the motor-simulation theory of Jeannerod [Neuroimage 14 (2001)], which proposes that perceiving actions involves neural simulation of the same action by the observer, thereby explaining the parallel between actions observed and actions imaged at the representational level.

Adolescent↗

PubMed1977

Observers' focus of attention in the simulation of self-perception.

This research was designed to assess the effects of a manipulation of observers' focus of attention--from a focus on the actor to a focus on the actor's situation--upon observers' attributions of attitude to an actor in a simulation of a forced-compliance cognitive dissonance experiment. Observers induced through empathy instructions to focus attention on the actor's situation inferred less actor attitude positivity than did observers given no specific observational set. In addition, situation-focused observers inferred that the actor's attitude was directly related to reward magnitude, whereas actor-focused observers inferred that the actor's attitude was inversely related to reward magnitude. An extension of self-perception theory, offered as an interpretation of these and other results, suggested that motivation attribution made by actors and observers in dissonance and simulation studies are dependent on focus of attention. The attributions made by actor-focused observers simulate those of objectively self-aware actors and are based upon perceived intrinsic motivation; the attributions of situation-focused observers simulate those of subjectively self-aware actors and are based upon perceived extrinsic motivation.

Attention↗

PubMed2005

Effector-dependent learning by observation of a finger movement sequence.

Can observational learning be effector dependent? In 3 experiments, observers watched a model respond to a 6-item unique sequence in a serial reaction time task. Their sequence knowledge was then compared with that of controls who had performed an unrelated task or observed a model responding to random targets. Observational learning was indicated when the introduction of a new sequence was associated with more reaction time elevation in observers than in controls. The authors found evidence of observational learning only when observers used the finger movement sequence that they observed during training, not when they responded at the same sequence of locations using different digits. Free generation and recognition tests also detected observational learning. These results imply that observational learning can be both explicit and effector dependent.

Adult↗

PubMed2003

Computer aided detection of masses in mammography using subregion Hotelling observers.

We propose to investigate the use of the subregion Hotelling observer for the basis of a computer aided detection scheme for masses in mammography. A database of 1320 regions of interest (ROIs) was selected from the DDSM database collected by the University of South Florida using the Lumisys scanner cases. The breakdown of the cases was as follows: 656 normal ROIs, 307 benign ROIs, and 357 cancer ROIs. Each ROI was extracted at a size of 1024 x 1024 pixels and sub-sampled to 128 x 128 pixels. For the detection task, cancer and benign cases were considered positive and normal was considered negative. All positive cases had the lesion centered in the ROI. We chose to investigate the subregion Hotelling observer as a classifier to detect masses. The Hotelling observer incorporates information about the signal, the background, and the noise correlation for prediction of positive and negative and is the optimal detector when these are known. For our study, 225 subregion Hotelling observers were set up in a 15 x 15 grid across the center of the ROIs. Each separate observer was designed to "observe," or discriminate, an 8 x 8 pixel area of the image. A leave one out training and testing methodology was used to generate 225 "features," where each feature is the output of the individual observers. The 225 features derived from separate Hotelling observers were then narrowed down by using forward searching linear discriminants (LDs). The reduced set of features was then analyzed using an additional LD with receiver operating characteristic (ROC) analysis. The 225 Hotelling observer features were searched by the forward searching LD, which selected a subset of 37 features. This subset of 37 features was then analyzed using an additional LD, which gave a ROC area under the curve of 0.9412 +/- 0.006 and a partial area of 0.6728. Additionally, at 98% sensitivity the overall classifier had a specificity of 55.9% and a positive predictive value of 69.3%. Preliminary results suggest that using subregion Hotelling observers in combination with LDs can provide a strong backbone for a CAD scheme to help radiologists with detection. Such a system could be used in conjunction with CAD systems for false positive reduction.

Algorithms↗

PubMed2006

Eye movements when observing predictable and unpredictable actions.

We previously showed that, when observers watch an actor performing a predictable block-stacking task, the coordination between the observer's gaze and the actor's hand is similar to the coordination between the actor's gaze and hand. Both the observer and the actor direct gaze to forthcoming grasp and block landing sites and shift their gaze to the next grasp or landing site at around the time the hand contacts the block or the block contacts the landing site. Here we compare observers' gaze behavior in a block manipulation task when the observers did and when they did not know, in advance, which of two blocks the actor would pick up first. In both cases, observers managed to fixate the target ahead of the actor's hand and showed proactive gaze behavior. However, these target fixations occurred later, relative to the actor's movement, when observers did not know the target block in advance. In perceptual tests, in which observers watched animations of the actor reaching partway to the target and had to guess which block was the target, we found that the time at which observers were able to correctly do so was very similar to the time at which they would make saccades to the target block. Overall, our results indicate that observers use gaze in a fashion that is appropriate for hand movement planning and control. This in turn suggests that they implement representations of the manual actions required in the task and representations that direct task-specific eye movements.

Adult↗

PubMed2005

Assessing observational studies of medical treatments.

BACKGROUND: Previous studies have assessed the validity of the observational study design by comparing results of studies using this design to results from randomized controlled trials. The present study examined design features of observational studies that could have influenced these comparisons. METHODS: To find at least 4 observational studies that evaluated the same treatment, we reviewed meta-analyses comparing observational studies and randomized controlled trials for the assessment of medical treatments. Details critical for interpretation of these studies were abstracted and analyzed qualitatively. RESULTS: Individual articles reviewed included 61 observational studies that assessed 10 treatment comparisons evaluated in two studies comparing randomized controlled trials and observational studies. The majority of studies did not report the following information: details of primary and ancillary treatments, outcome definitions, length of follow-up, inclusion/exclusion criteria, patient characteristics relevant to prognosis or treatment response, or assessment of possible confounding. When information was reported, variations in treatment specifics, outcome definition or confounding were identified as possible causes of differences between observational studies and randomized controlled trials, and of heterogeneity in observational studies. CONCLUSION: Reporting of observational studies of medical treatments was often inadequate to compare study designs or allow other meaningful interpretation of results. All observational studies should report details of treatment, outcome assessment, patient characteristics, and confounding assessment.

Journal Article↗

PubMed2001

Toward a consensus on reference values for thyroid volume in iodine-replete schoolchildren: results of a workshop on inter-observer and inter-equipment variation in sonographic measurement of thyroid volume.

OBJECTIVE: Interpretation of thyroid ultrasonography for assessing goiter prevalence requires valid reference criteria from iodine-sufficient populations. Reports have suggested the current reference criteria for thyroid volume (T(vol)) of WHO/ICCIDD (International Council for the Control of Iodine Deficiency Disorders) may be too high. Our objective was to determine if inter-observer and/or inter-equipment variability contributes to the disagreement in sonographic T(vol) in children reported from iodine-sufficient areas. DESIGN: A 2-day workshop in which four experienced ultrasound examiners from around Europe measured T(vol) in 45 6--12-year-old Swiss schoolchildren using four different portable ultrasound machines. One of the participating examiners (observer A) had generated the T(vol) data in European children that are the basis for the WHO/ICCIDD reference criteria. METHODS: Sonographic T(vol) was measured in each child by all four examiners on all four machines. Six hundred and eighty-four examinations were completed, with examiners having no knowledge of one another's results. Inter-observer and inter-equipment variation was calculated. RESULTS: Mean inter-equipment variation in T(vol) was 15.2% (95% CI: 14.1, 16.3%). There were no significant differences in T(vol) between equipment (P=0.51). For all observers, the mean inter-observer variation in T(vol) was 25.6% (95% CI: 23.9, 27.2%). At all ages and all body surface areas, there was a large systematic measurement bias (+30% volume) between the mean T(vol) of observer A and the mean Tvol of observers B, C and D. Reanalysis using data from observers B, C and D reduced the mean inter-observer variation in T(vol) to 13.3% (95% CI: 11.9, 14.7%). A correction factor for the systematic difference of operator A for the P50 and P97 of T(vol) was estimated using analysis of covariance. When applied to the WHO/ICCIDD reference data, it sharply reduced the discrepancy between the WHO/ICCIDD criteria and those from other iodine-sufficient children around the world. CONCLUSIONS: Inter-equipment error contributes minimally to reported differences in sonographic T(vol). Even among experienced examiners, inter-observer variation in sonographic T(vol) in children can be high, and probably contributes to the current disagreement on normative values in iodine-sufficient children. A systematic bias at least partially explains why the WHO/ICCIDD reference data differ from those reported from other iodine-sufficient children around the world. The findings argue strongly for the standardization of methods used for sonographic measurement of T(vol) in children.

Child↗

PubMed1981

The effects of instructions and calculation procedures on observers' accuracy, agreement, and calculation correctness.

Although the quality of observational data is generally evaluated by observer agreement, measures of both observer agreement and accuracy were available in the present study. Videotapes with a criterion protocol were coded by 16 observers. All observers calculated agreement scores both on their own and their partner's data and on a contrived data set misrepresented as data collected by other observers. Compared with agreement scores calculated by the experimenter, observers erroneously inflated their own agreement scores and deflated the agreement scores on the contrived data. Half of the observers (n = 8) had been given instructions emphasizing the importance of accuracy during observation while the other half had been given instructions emphasizing interobserver agreement. Accuracy exceeded agreement for the former group, whereas agreement exceeded accuracy for the latter group. The implications are that agreement should be calculated by the experimenter and that the accuracy-agreement relationship can be altered by differential observer instructions.

Journal Article↗

PubMed1962

Observing responses in pigeons.

Pigeons were trained on an observing-response procedure in which periods of VR 100 and EXT alternated unpredictably during a white light (mixed stimulus). During VR 100, responses on a food-producing key (the first key) were intermittently reinforced. Responses on the observing key (the second key) produced a green light (positive stimulus) when VR 100 was in effect, and a red light (negative stimulus) for EXT. The birds did not respond on either key during the negative stimulus, but they responded on the food-producing key when the positive stimulus appeared. When observing responses produced the positive or negative stimulus on FR, observing responses were maintained until the FR reached a maximum; beyond this, only food-producing responses occurred. When observing responses did not produce either stimulus, the observing-response rates fell to zero. With prolonged exposure to an FR 20 schedule of observing, observing-response rates during EXT were higher than during VR 100. Chlorpromazine hydrochloride decreased the total response output but markedly increased observing-response rates except when it was administered before sessions of observing response extinction.

Animals↗

PubMed1991

The effects of diazepam and triazolam on repeated acquisition and performance of response sequences with an observing response.

Drugs often disrupt the acquisition of new response sequences at doses that fail to disrupt the performance of a previously acquired response sequence. This selective drug effect may result from differences in the control exerted by the stimuli presented after each response in the acquisition and performance sequences. To examine the function of these stimuli, an observing procedure was incorporated into a multiple schedule of repeated acquisition and performance of response sequences, in which stimulus presentations were contingent upon an observing response. Three experiments were conducted with humans. Experiment 1 compared responding with and without the observing contingency. No difference was found in the overall percentage of errors across the two conditions. Within the observing condition, observing behaviour was maintained in the acquisition component as long as errors occurred, but was not maintained in the performance component. Experiment 2 examined whether a contingency that increased errors also would increase observing in both the acquisition and performance components. Specifically, reinforcer delivery in each component was contingent upon emitting 10 correct responses and one, two, or four errors. Observing responses increased in the acquisition component as the error requirement increased, whereas observing responses in the performance component increased only when the error requirement was four. Experiment 3 assessed the effects of diazepam (0, 7.5, 15, and 30 mg/70 kg, p.o.) and triazolam (0, 0.375, and 0.75 mg/70 kg, p.o.) on repeated acquisition and performance baselines with the observing contingency. Selective drug effects were obtained in this modified procedure; that is, the percentage of errors in the acquisition component increased at doses that failed to affect the percentage of errors in the performance components. Importantly, drug effects were selective, even though observing responses were not emitted in the performance component and, hence, the stimulus presentations did not occur in that component. These findings suggest that alternative explanations for these differential effects are needed; in that regard, a response-unit account of the selective drug effects is discussed.

Adult↗

PubMed1998

[Prognostic factors for hearing preservation following observation-only versus stereotactic irradiation (STI) in patients with acoustic neuroma].

Prognostic factors for hearing preservation following observation-only versus STI were compared in patients with acoustic neuroma. There were 48 patients with acoustic neuroma treated by fractionated STI. Between 1991 and 1997, patients were given 36 Gy in 20 fractions over 5 weeks (36 Gy/20 Fr/5 wks) to 44 Gy/22 Fr/6 wks followed by a 4 Gy boost. A linear accelerator was used for irradiation. Twenty-three patients with acoustic neuroma who were followed without any treatment (observation-only group) were selected as matched controls. The largest hearing loss was observed at the frequency of 2 kHz in the observation-only group and at 1-2 kHz in the STI group. Hearing loss at 1 kHz was more frequent in the STI group (p < 0.01). There were no significant prognostic factors which predicted hearing preservation in the observation-only group. Stereotactic irradiation has been suggested to damage to cochlear nerve function in patients whose cochlear nerve had been impaired already. Tumor control rate of STI appeared to be as good as single fraction radiosurgery rates in the literature and better than in the observation-only group. Hearing preservation rate in the STI group was as good as in the observation-only group and appeared to be better than single fraction radiosurgery. In conclusion, because there were no factors predictive of hearing preservation in the observation-only group, it is difficult to select patients for observation only. Fractionated STI is potentially the treatment of choice, resulting in the same hearing preservation rate as achieved with observation only, although longer follow-up periods are needed.

Adult↗

PubMed1981

Further definition of history and observation variables in assessing febrile children.

The experienced clinician makes a judgment (hereafter called overall assessment [OA]) about the degree of illness of a febrile child prior to physical examination. In order to define the history and observation variables on which OA is based, 262 febrile children less than or equal to 24 months of age were evaluated simultaneously by multiple observers including attending pediatricians, practicing pediatricians, pediatric house officers, and nurses. The observer listed history and observation variables he/she thought most important in making an OA on a blank, lined form and then scored those variables and OA as normal, or mildly, moderately, or severely impaired. Scoring for observation rather than history variables was better correlated with scoring for OA and serious illness. The observation variables most frequently mentioned by all observers were the child's "looking at the observer" and "looking around the room." There were 20 observation variables frequently mentioned, the scoring of which significantly correlated with scoring for OA; four of these 20 variables related to eye function. The child's response to a stimulus was noted in 105/186 different observation variables listed; both the attending pediatrician and the house officer scored these stimulus-response variables significantly different in children with, vs those without, serious illnesses. For attending pediatricians, house officers, and nurses, serious illness was five to seven times as likely if an OA of moderate or severe impairment was made than if it were not made. OA is a key skill in evaluating febrile children; these data identify variables on which OA is based, document the importance of assessing eye function in young, febrile children, and demonstrate that eye function is one key type of stimulus-response behavior on which the pediatrician as clinician and developmentalist relies to make judgments about febrile children.

Child Development↗