Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Proxy”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Factitious illness by proxy presenting as anorexia and polydipsia by proxy.

Factitious illness by proxy is a highly pathological form of parent-child relationship. To our knowledge no former case of polydipsia by proxy has been published. The case of a 2-y-old boy suffering from malnutrition due to displacement of maternal anorexia and polydipsia is presented. Child psychiatric evaluation found cognitive delay and psycho-social impairment in the child, as well as a severe mother-child relationship disturbance. Psychological assessment showed a personality disorder with depressive and paranoid features in the mother. The father was described as a schizoid personality. The possible mechanisms of displacement are hypothesized.

Anorexia↗

'Battered pets': Munchausen syndrome by proxy (factitious illness by proxy).

Nine cases of suspected Munchausen syndrome by proxy (MSBP), involving pets as proxies, were identified among 448 cases of non-accidental injury to small animals. These cases, recorded by a random sample of small animal practitioners in the UK, demonstrated several combinations of features, including attention-seeking behaviour by the owner, real and apparently factitious clinical signs, deliberate injury, markedly abnormal biochemical profiles, serial incidents, interference with surgical sites, recovery after separation from the owner, and 'veterinarian-shopping' by the owner. All of these features are consistent with those identified in the well documented MSBP in which children are the victims. Furthermore, one of the cases involved serial attempts at poisoning other animals and a child.

Animals↗

Outcome of psychiatric intervention in factitious illness by proxy (Munchausen's syndrome by proxy).

OBJECTIVE: To determine the outcome for children after psychiatric intervention in cases of factitious illness by proxy. METHODS: All 17 children from 16 families, selected for admission to the Park Hospital Oxford family unit 1992-96 were followed up after a mean of 27 months. Information was obtained on the children and their carers from general practitioners, social workers or both; 13 of the children and carers were interviewed. RESULTS: All patients were at the severe end of the abuse spectrum; 12 involving direct induction of illness, 1 tampering with samples to mimic illness, and 4 fabrication of symptoms. The biological mother was the abuser in all cases. Four children and their parents had been initially admitted for assessment, and 13 for treatment to decide whether family reunification was viable. The 4 assessments clarified diagnosis, enabling improved care plans to be made. Of the 13 treatment cases, 10 were reunited with parents after a mean of 71/2 weeks' admission, whereas 3 were discharged to out of home care. There was a further episode of induced illness in 1 of the reunited children. Although some mothers had continuing mental health difficulties, only 1 of the other reunited cases had appreciable parent-child relationship difficulties (not requiring referral to psychiatric services). The children did well in their development, growth, and adjustment. CONCLUSION: Family reunification is feasible for certain cases, but long term follow up is necessary to ensure the child's safety and to identify deterioration in parent's mental health. The outcome for reunited children compared well with reported untreated cases.

Attitude to Health↗

Factitious illness by proxy. Munchausen syndrome by proxy.

BACKGROUND: Since 1977 a literature has grown describing examples of factitious illness by proxy (FIP). METHOD: The literature in English was searched using MEDLINE and supplemented by a manual search. Extracted data focused on terminology of a spectrum of behaviours, clinical features and psychopathology of perpetrators. RESULTS: There has been difficulty with the use of terminology and classification of psychiatric disorders. CONCLUSIONS: The spectrum of FIP is wide. Suggestions are made for the use of terminology and classification when FIP is identified.

Adult↗

Proxy reporting in after-death interviews: the use of proxy respondents in retrospective assessment of chronic diseases and symptom burden in the terminal phase of life.

This study evaluates the quality of data obtained from after-death interviews with significant others of deceased older persons regarding the prevalence of chronic diseases and symptoms in the terminal phase of life. These data are compared with reports from physicians and earlier self-reports from the deceased person. There were significant increases in nonresponse and nonavailability of significant others for decedents who had been divorced or had never been married, thus introducing some selection bias. At the level of the total sample, significant others seem to give accurate information about the prevalence of chronic diseases when compared with self-reports and reports from physicians. At the level of the individual sample member, after-death interviews with significant others provide valid information for the assessment of the prevalence of malignant neoplasms, diabetes mellitus, chronic obstructive pulmonary disease and cerebrovascular disease, but not for osteo- and rheumatoid arthritis and artherosclerotic disease. At the level of the total sample, the prevalence of symptoms assessed by significant others did not differ greatly from the assessment made by physicians. However, at the level of the individual sample member, the validity of symptom assessment by significant others could not be supported by data obtained from the physicians. With regard to the type of significant others interviewed, children reported more symptoms than partners. The use of significant others in after-death interviews can be a valid method with regard to the assessment of chronic diseases and symptoms on a group level. On an individual level this can be concluded only for chronic diseases with clearly observable consequences.

Aged↗

Evaluation of proxy responses to the Stroke Impact Scale.

BACKGROUND AND PURPOSE: The purposes of this study were to compare proxy-patient responses on each domain of the Stroke Impact Scale (SIS) and the SIS-16, estimate the bias, and evaluate the validity of proxy scores. METHODS: Two hundred eighty-seven patient and proxy pairs from the Kansas City Stroke Registry participated in the study. All patients were assessed in their home or nursing facility between 90 and 120 days after stroke with the use of the modified Rankin Scale Motricity Index (strength), Barthel Index (activities of daily living), Lawton assessment (instrumental activities of daily living), Folstein Mini-Mental State Examination (cognition), and the SIS. Eligible proxies were individuals who were aged > or =18 years, had known the patient for at least 1 year, and saw the patient at least once each week. All proxy interviews were conducted within 7 days of (before or after) the patient's interview. RESULTS: Three hundred seventy-seven patients from the Kansas City Stroke Registry were eligible for the study. Seventy-seven patients or proxies refused participation. Thirteen patients of the consenting patient-proxy pairs were too aphasic or cognitively impaired to complete the interviews and were dropped from the study. Proxies scored patients as more severely affected than patients scored themselves on the SIS-16 and in 7 of 8 domains of the full SIS (5 were statistically significant at alpha=0.05). The proxy bias toward overrating the severity of the patient's condition tended to increase as the severity of the stroke increased. However, the magnitude of the biases between patient and proxy means, as measured by effect size, was small (range, -0.1 to 0.4). The strength of the agreement, as measured by intraclass correlation coefficients, between proxy and patient ranged from 0.50 to 0.83. Agreement was best for the observable physical domains. Both patient and proxy scores in all domains were significantly different across Rankin categories. Concurrent validity for both patient and proxy correlations with the Folstein Mini-Mental State Examination, Barthel Index, Lawton instrumental activities of daily living, and Motricity Index was good to excellent (range, 0.37 to 0.78). CONCLUSIONS: Proxies provide valid information for assessment of stroke outcomes. There are significant differences between patient and proxy reporting on SIS domains and the SIS-16. However, the observed biases are small and not clinically meaningful.

Activities of Daily Living↗

Problems in using health survey questionnaires in older patients with physical disabilities. Can proxies be used to complete the SF-36?

BACKGROUND: The SF-36 Health Survey questionnaire has been proposed as a generic measure of health outcome. However, poor rates of return and high levels of missing data have been found in elderly subjects and, even with face-to-face interview, reliability and validity may still be disappointing, particularly in cognitively impaired patients. These patients may be the very patients whose quality of life is most affected by their illness and their exclusion will lead to biased evaluation of health status. A possible alternative to total exclusion is the use of a proxy to answer on the patient's behalf, but few studies of older people have systematically studied patient-proxy agreement. OBJECTIVE: To compare the agreement between patients, lay and professional proxies when assessing the health status of patients with the SF-36. METHODS: The SF-36 was administered by interview to 164 cognitively normal, elderly patients (Mini-mental State Examination 24 or more) referred for physical rehabilitation. The SF-36 was also completed by a patient-designated lay proxy (by post) and a professional proxy. Agreement between proxies and patients was measured by intraclass correlation coefficients (ICCs), and a bias index. RESULTS: Professional proxies were better able to predict the patients' responses than were the lay proxies. Criterion levels of agreement (ICC 0.4 or over) were attained for four of the eight dimensions of the SF-36 by professional proxies, but for only one dimension by lay proxies. In professional proxies, the magnitude of the bias was absent or slight (<0.2) for six of the eight dimensions of the SF-36 with a small (0.2-0.49) negative bias for the other two. Lay proxies showed a negative bias (i.e. they reported poorer function than did the patients themselves) for seven of the eight dimensions of the SF-36 (small in two and moderate (0.5-0.79) in five). CONCLUSIONS: For group comparisons using the SF-36, professional proxies might be considered when patients cannot answer reliably for themselves. However, in the present study, lay proxy performance on a postal questionnaire showed a strong tendency to negative bias. Further research is required to define the limitations and potentials of proxy completion of health status questionnaires.

Aged↗

Enhancement of proxy appointment for older persons: physician counselling in the ambulatory setting.

OBJECTIVE: To determine the effectiveness of physician-initiated counselling on the rate of health care proxy appointment. DESIGN: Observational study of an intervention in a convenience sample. SETTING: A geriatric outpatient clinic in a tertiary care teaching hospital, New York, New York. PARTICIPANTS: A total of 687 patients enrolled in the geriatric clinic during the study period March 1991 through June 1993. INTERVENTION: Physician counselling about the New York State Health Care Proxy Law, distribution of educational materials and healthcare proxy forms, and reminders in 331 of 466 eligible patients. MEASUREMENTS: Rate of healthcare proxy appointment in eligible and counselled groups; predictors of appointment and non-appointment; time elapsed from counselling to appointment; reasons for non-appointment; characteristics of the proxy appointment process. RESULTS: A healthcare proxy was appointed for 31.5% of patients eligible for counselling and for 44% of patients who actually received the intervention, compared with a 2.3% proxy appointment rate at baseline. Eighty-one percent of the patients completing the proxy appointment process did so at or before their third clinic return visit after the counselling intervention. Of the counselled patients who did not appoint a proxy, 25% explicitly declined, and 75% had not come to a decision by the end of the study period. Proxy completion was associated with ethnicity, education, and more frequent clinic visits. Of those who appointed a proxy, 97% had good or fair comprehension of the procedure, 92% discussed the appointment with their designees, 63% appointed a daughter or son, and 80% discussed their wishes for care at the end of life with their proxy. CONCLUSIONS: Physician counselling of older outpatients is an effective means of increasing healthcare proxy appointments.

Advance Care Planning↗

Reliability of data from proxy respondents in an international case-control study of cardiovascular disease and oral contraceptives. World Health Organization Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception.

STUDY OBJECTIVES: To evaluate the reliability of data supplied in a case-control study by proxy respondents for cases who were too ill to do so themselves. DESIGN: A hospital based, case-control study of the current use of oral contraceptives (OC) and cardiovascular diseases. Data from "true" controls matched to a subset of cases were compared with those supplied by proxy respondents about the true controls. SETTING: Hospitals in 21 centres from Africa, Asia, Europe, and Latin America. PATIENTS AND PARTICIPANTS: For a subset of cases, 403 pairs of controls-one "true" and one proxy-were interviewed. "True" controls were matched by age, place, and time of admission and were admitted with 1 of 27 permissible diagnoses not associated with OC use. Proxy controls were either relatives or friends of true controls. MAIN RESULTS: Levels of concordance between data from proxy and true controls were high for most variables regarding recent events, including current OC use, but were greatly diminished when detailed information, particularly from the past, was required. Husbands were usually the best proxy, although this was question-specific. The sensitivity and specificity of proxy responses were 93% (95% confidence intervals: 77%, 99%) and 100% (98%, 100%) respectively, for current use of OC. Assuming the misclassification of current OC use by proxy cases is similar to that produced by proxy controls, the estimated impact of using proxy data on risk estimates associated with current OC use was to bias the overall estimate of risk of stroke by less than 3% and the risks of both acute myocardial infarction and venous thromboembolism by less than 1%. CONCLUSIONS: Friends or relatives, and particularly husbands, provided reliable information when used as proxy respondents for young women. The estimated impact of misclassification by proxy respondents on overall risk estimates in the WHO collaborative study was less than that which would have arisen if information from proxy respondents had not been used.

Adult↗

Agreement between self reports and proxy reports of quality of life in epilepsy patients.

Agreement between self reports and proxy reports of quality of life was examined in a sample of 292 patients with epilepsy and their designated proxies. Patients and proxies completed an 89-item Quality of Life Inventory (QOLIE-89), with the items rephrased for the proxy. Results reveal moderate correlations (product-moment r ranging from 0.29 to 0.56 for 17 multi-item scales) between self reports and proxy reports. Agreement was good for measures of function that are directly observable and relatively poor for more subjective measures. Mean scale scores were significantly different between patients and proxies for only five of 17 multi-item scales. Proxy respondents systematically reported better functioning than did patients in three scales assessing cognitive functioning (all p < 0.001). By contrast, patients reported more positive health perceptions and less seizure distress than proxies. Patient educational attainment correlated inversely with degree of disagreement between patient and proxy reports for six of the 17 QOL scales and for the overall score. In addition, proxy educational attainment correlated positively with agreement for four scales. This study indicates that for group level comparisons, proxy respondents can be substituted for adults with epilepsy having low to moderate seizure frequency. However, for individual level assessments proxies should be used with caution.

Adolescent↗

Proxy reliability: health-related quality of life (HRQoL) measures for people with disability.

OBJECTIVES: Research and surveillance activities sometimes require that proxy respondents provide key exposure or outcome information, especially for studies of people with disability (PWD). In this study, we compared the health-related quality of life (HRQoL) responses of index PWD to proxies. METHODS: Subjects were selected from nursing home, other assisted living residences, and from several clinic samples of PWD. Each index identified one or more proxy respondents. Computer-assisted interviews used a random order of measures. Proxy reliability was measured by intraclass correlation (ICC) and kappa statistics. HRQoL measures tested included the surveillance questions of the Behavioral Risk Factor Surveillance System (BRFSS), basic and instrumental activities of daily living (ADLs and IADLs), medical outcomes study short-form 36 and 12 (SF-36 and SF-12). RESULTS: A total of 131 index-proxy sets were completed. In general, agreement and reliability of proxy responses to the PWD tended to be best for relatives, with friends lower, and health care proxies lowest. For example, the ICC for the physical functioning scale of the SF-36 was 0.68 for relatives, 0.51 for friends, and 0.40 for healthcare proxies. There was a tendency for proxies to overestimate impairment and underestimate HRQoL. This pattern was reversed for measures of pain, which proxies consistently underestimated. The pattern among instruments, proxy types, and HRQoL domains was complex, and individual measures vary from these general results. CONCLUSIONS: We suggest caution when using proxy respondents for HRQoL, especially those measuring more subjective domains.

Activities of Daily Living↗

Completeness and accuracy of interview data from proxy respondents: demographic, medical, and life-style factors.

To evaluate the quality of exposure data provided by proxy respondents, we used a dual interview protocol in a case-control study of subarachnoid hemorrhage. All control subjects and their proxy respondents were interviewed (N = 283 control-proxy pairs), as were the cases who were able to provide their own information and their proxy respondents (N = 68 case-proxy pairs). The reliability of proxy-derived data was excellent for demographic and body habitus measures (kappa or intraclass correlation range = 0.86-0.99), and all aspects of cigarette smoking history (range = 0.79-0.93). Proxy reliability was somewhat lower for questions regarding medications and hormone preparations (range = 0.55-0.88), alcohol consumption (range = 0.52-0.82), and recreational physical activity (range = 0.55-0.67). Proxy reliability varied according to the relationship of the proxy to the index subject. Relative to the index subjects, proxy respondents tended to underreport the presence or level of exposure. For most exposures, odds ratios computed with proxy-derived data were similar in magnitude to odds ratios obtained with index subject data; important bias due to differential nonresponse or differential misclassification was suggested only for questions regarding hormone replacement therapy. Epidemiologic studies that rely on proxy respondents may require more subjects to offset the effect of nondifferential nonresponse and misclassification on the precision of effect estimates.

Adolescent↗

Proxies' decisions about clinical research participation for their charges.

OBJECTIVE: To examine the process by which proxies decide about their charges' participation in clinical research. DESIGN: Using eight hypothetical research studies encompassing a variety of risks and benefits, we interviewed 315 competent persons > or = 65 years old (charges) and, separately, the individuals who would be designated as their proxies if the charges were to become incompetent. The proxies were asked what they thought their charges would decide and what decisions they would make for their charges and for their own participation. SETTINGS: A medical house-call program, two apartment complexes, and three nursing homes. PARTICIPANTS: Charges > or = 65 years old and their proxies. MAIN OUTCOME MEASURE: Comparison of decisions made by charges and by proxies for their charges. RESULTS: The agreement between the proxies' and charges' decisions was not significantly different from random agreement (range of kappa statistics, 0.05-0.15). Rather, proxies' decisions for their charges were significantly related to the proxies' decisions for themselves (kappas, 0.52-0.86). When the paired proxies' and charges' decisions differed, the proxies were protective, more frequently refusing their charges' participation in the perceived riskier research studies. CONCLUSIONS: Proxies did not know what their charges would decide. Their choices for the charges related more to the proxies' decisions about their own participation (which they knew) than to the decisions of their charges (which they didn't know). This is similar to the process of a reasonable person making the decision, a characteristic of decisions made in the best interests of the patient.

Adult↗

Are proxy assessments of health status after stroke with the EuroQol questionnaire feasible, accurate, and unbiased?

BACKGROUND AND PURPOSE: It is often difficult to determine the health-related quality of life (HRQoL) of stroke patients because physical and cognitive problems limit their ability to complete complex questionnaires. A proxy, such as a family member or caregiver, may be able to give an estimate of the patients' health status. We therefore examined the agreement between the HRQoL as assessed by a series of patients and that assessed by their proxies. METHODS: We studied the validity of the EuroQol in a series of 152 patients from our prospective registry of patients with first (or recurrent) stroke. We asked patients to ensure that a friend or relative (a proxy) who knew them well was available at the time of the interview. We asked each proxy to complete a EuroQol questionnaire independently on behalf of the patient. RESULTS: Proxies completed forms for 130 patients (86%). Agreement between responses from the patients and those from their proxies was better for patients who were able to self-complete the EuroQol than for patients who required the EuroQol to be administered by interview. For both groups, agreement was best for the self-care domain and worst for the domain that assessed psychological outcome. For the more severely affected patients, agreement was only fair for the pain and social functioning domains and no better than chance alone for the psychological functioning domain (kappa = 0.05, 95% confidence interval, 0 to 0.43). Patients tended to rate their own health status as better than their proxies did (P < .05). CONCLUSIONS: We found moderate agreement between responses from patients and those from their proxies for the more directly observable domains of the EuroQol. Proxy agreement was less good for the more subjective domains. In health surveys, allowing responses by a proxy increases response rate. However, the disadvantages inherent in the use of proxy responses must be considered carefully. In general, some domains of HRQoL information obtained from a proxy may be sufficiently valid and unbiased to be useable in most types of trials and surveys.

Caregivers↗

Assessing quality of life after stroke. The value and limitations of proxy ratings.

BACKGROUND AND PURPOSE: Because many stroke survivors have cognitive and communication disorders, self-reported information on a patient's quality of life (QL) cannot always be obtained. Proxy ratings may be used to prevent exclusion of this highly relevant subgroup of patients from QL studies. The purpose of this study was to evaluate both the value and possible limitations of such proxy ratings. METHODS: The patient sample was composed of 437 patients who had suffered a stroke 6 months earlier. QL was assessed by means of the Sickness Impact Profile (SIP). For 108 patients who were not communicative because of cognitive or linguistic deficits, proxy ratings on the SIP were provided by the patients' significant others. For 228 of the 329 communicative patients, both self-reported and proxy SIP ratings were obtained. RESULTS: When mean SIP scores for patients with both self-reported and proxy-derived data available were compared, the proxy mean scores were generally in close agreement with those of the patients. However, systematic differences were noted for several SIP scales, with proxies rating patients as having more QL impairments than the patients themselves. Intraclass correlations were moderate to high for most SIP subscales (average intraclass correlation coefficient [ICC] = .63), the physical (ICC = .85) and psychosocial dimensions (ICC = .61), and the total SIP score (ICC = .77). The proxy SIP scores were sensitive to differences in patients' functional health, which supports the validity of these ratings. For all patients combined, more QL impairments were found for patients with supratentorial cortical or subcortical infarctions and hemorrhages than for patients with lacunar infarctions and infratentorial strokes. Although proxy respondents were more frequently needed for patients with the first two types of stroke, we found no evidence of biased results as a consequence of an unbalanced use of proxy respondents across the different types of stroke. CONCLUSIONS: These results suggest that the benefits of using proxy ratings for noncommunicative patients outweigh their limitations. The findings stress the need for inclusion of this important subgroup of patients in QL studies. Their significant others are able to provide useful information on these patients' QL.

Adolescent↗

The use of proxy responses for aged patients in long-term care settings.

To evaluate the utility of proxy responses for aged residing in a long-term care institution, 106 non-severely cognitively impaired institutionalized patients and their designated proxies were interviewed using an identical interview schedule (53 pairs of patient-proxy interviews). Questions on selected diseases, symptoms and demographic characteristics were included and agreement between respondents and proxies was evaluated. Proxies attempted to provide information on most questions. For many medical diseases and demographic characteristics, proxies provided information which agreed with that provided by patients. However, proxies had more difficulty providing comparable answers about symptoms. It is concluded that a proxy's knowledge of a patient varies by topic. While proxy reports of specific diseases are consistent with the patient's responses, proxy reports of subjective items such as symptoms are not. Recommendations for future research in this area and the importance of these conclusions for other researchers relying on proxy reports are discussed.

Aged↗

Substituting proxy ratings for patient ratings in cancer clinical trials: an analysis based on a Southwest Oncology Group trial in patients with brain metastases.

In studies of the effect of cancer treatment in the advanced disease setting, researchers have attempted to avoid missing data for quality of life (QOL) assessments by either substituting proxy for patient assessments from the outset or by interspersing proxy measures when patients are unable to respond. Although poor agreement between patient and proxy assessments has been amply demonstrated in the literature, interest in using proxy measures persists. Completion of the Spitzer QL-Index by a small sample of patients with brain metastases and family member proxies provided data for evaluating the ability to substitute proxy for patient QOL assessments. These data cannot address treatment efficacy due to the modest sample size. Rather, the analyses serve to alert researchers to the important distinction (in a clinical trial setting) between agreement and the use of the proxy as a surrogate. We present several methods for evaluating the accuracy of proxy measures and for identifying other sources of error and bias that may vary with time or with treatment arm. Lin's concordance correlation coefficient suggests that proxies are generally a poor substitute for capturing a patient's perspective of his/her QOL. A longitudinal analysis suggests that the use of proxy rather than patient responses could lead to different conclusions concerning radiation therapy's effect on QOL.

Adult↗