Impact of insurance and supply of health professionals on coverage of treatment for hypertension in Mexico: population based study

OBJECTIVE

To examine the independent and combined contributions of insurance status and supply of health professionals on coverage of antihypertensive treatment among adults in Mexico.

DESIGN

Population based study.

SETTING

Mexico.

PARTICIPANTS

4032 hypertensive adults (2967 uninsured and 1065 insured): 1065 uninsured adults matched with 1065 adults insured through Seguro Popular, a programme to expand health insurance coverage to uninsured people in Mexico.

MAIN OUTCOME MEASURES

Coverage of antihypertensive treatment and coverage of antihypertensive treatment with control of blood pressure.

RESULTS

Rates of treatment for hypertension varied by insurance status and supply of health professionals. Hypertensive adults insured through Seguro Popular had a significantly higher probability of receiving antihypertensive treatment (odds ratio 1.50, 95% confidence interval 1.27 to 1.78) and receiving antihypertensive treatment with control of blood pressure (1.35, 1.00 to 1.82). Greater supply of health professionals in areas with coverage through Seguro Popular was a significant predictor of antihypertensive treatment after adjusting for covariates (1.49, 1.00 to 2.20).

CONCLUSIONS

Expansion of healthcare coverage to uninsured people in Mexico was associated with greater use of antihypertensive treatment and blood pressure control, particularly in areas with a greater supply of health professionals.

Depression and cost-related medication nonadherence in Medicare beneficiaries

CONTEXT

Treatment for depression can be expensive and depression can affect the use of other medical services, yet there is little information on how depression affects the prevalence of cost-related medication nonadherence (CRN) in elderly patients and patients with disabilities.

OBJECTIVE

To quantify the presence of CRN in depressed and nondepressed elderly Medicare beneficiaries and nonelderly Medicare beneficiaries with disabilities prior to the implementation of the Medicare Drug Benefit.

DESIGN AND SETTING

2004 Medicare Current Beneficiary Survey.

PARTICIPANTS

Depressed and nondepressed elderly Medicare beneficiaries and beneficiaries with disabilities.

MAIN OUTCOME MEASURES

Cost-related medication nonadherence included taking smaller doses or skipping doses of a prescription to make it last longer, or failing to fill a prescription because of cost, controlling for health insurance status, comorbid conditions, age, race, sex, and functional status.

RESULTS

In a nationally representative sample of 13 835 noninstitutionalized elderly Medicare enrollees and Medicare enrollees with disabilities, 44% of beneficiaries with disabilities and 13% of elderly beneficiaries reported being depressed during the previous year. Among enrollees with disabilities reporting depressive symptoms, 38% experienced CRN compared with 22% of enrollees with disabilities who did not report depressive symptoms. Among elderly enrollees who reported depressive symptoms, 19% experienced CRN, compared with 12% of elderly enrollees who did not report such symptoms. In adjusted analyses, depressive symptoms remained a significant predictor of CRN in both groups (persons with disabilities: odds ratio, 1.7; 95% confidence interval, 1.3-2.3; elderly persons: odds ratio, 1.4; 95% confidence interval, 1.1-1.7).

CONCLUSIONS

Depressive symptoms were associated with CRN in elderly Medicare enrollees and Medicare enrollees with disabilities. Providers should elicit information on economic barriers that might interfere with treatment of Medicare beneficiaries with depression.

Strategies for coping in a complex world: adherence behavior among older adults with chronic illness

BACKGROUND

Increasing numbers of medicines increase nonadherence. Little is known about how older adults manage multiple medicines for multiple illnesses.

OBJECTIVES

To explore how older adults with multiple illnesses make choices about medicines.

DESIGN

Semistructured interviews with older adults taking several medications. Accounts of respondents' medicine-taking behavior were collected.

PARTICIPANTS

Twenty community-dwelling seniors with health insurance, in Eastern Massachusetts, aged 67-90, (4-12 medicines, 3-9 comorbidities).

APPROACH

Qualitative analysis using constant comparison to explain real choices made about medicines in the past ("historical") and hypothetical ("future") choices.

RESULTS

Respondents reported both past ("historical") choices and hypothetical ("future") choices between medicines. Although people discussed effectiveness and future risk of the disease when prompted to prioritize their medicines (future choices), key factors leading to nonadherence (historical choices) were costs and side effects. Specific choices were generally dominated by 1 factor, and respondents rarely reported making explicit trade-offs between different factors. Factors affecting 1 choice were not necessarily the same as those affecting another choice in the same person. There was no evidence of "adherent" personalities.

CONCLUSION

Prescribing a new medicine, a change in provider or copayment can provoke new choices about both new and existing medications in older adults with multiple morbidities.

Provider and patient characteristics associated with antidepressant nonadherence: the impact of provider specialty

OBJECTIVE

Given the widespread use of anti-depressants in primary care and specialty populations, we sought to examine whether provider specialty and patient demographic and clinical characteristics were associated with nonadherence to antidepressant therapy.

METHOD

We conducted an observational cohort study of 11,878 patients enrolled in Harvard Pilgrim Health Care who were newly treated with antidepressants between May 2002 and May 2004. Using generalized estimating equations, we examined predictors of 2 types of anti-depressant nonadherence: (1) immediate non-adherence: never refilling an antidepressant prescription; and (2) 6-month nonadherence: refilling an antidepressant prescription at least once, but not satisfactorily completing a 6-month treatment episode.

RESULTS

Compared with patients treated by primary care physicians (PCP), being treated by a psychiatrist was associated with significantly lower odds of immediate nonadherence (PCP 18% vs. psychiatrist 13%). Being treated by another type of specialist was associated with significantly higher odds of both immediate (other specialist 23%) and 6-month nonadherence (PCP 53%, psychiatrist 49%, other specialist 62%). Treatment by multiple providers was associated with lower odds of nonadherence than being treated by only 1 provider. Younger patient age and use of pain medication were associated with greater nonadherence.

CONCLUSION

Rates of both immediate and 6-month nonadherence are high, and clinicians should emphasize the importance of continuing antidepressant treatment for a sufficient duration. Patients whose depression treatment is initiated by nonpsychiatric specialists may benefit from collaborative care models. These strategies may enable providers to better manage the long-term disability associated with their patients' depression.

Relationship between patient medication adherence and subsequent clinical inertia in type 2 diabetes glycemic management

OBJECTIVE

Clinical inertia has been identified as a critical barrier to glycemic control in type 2 diabetes. We assessed the relationship between patients' initial medication adherence and subsequent regimen intensification among patients with persistently elevated A1C levels.

RESEARCH DESIGN AND METHODS

We analyzed an inception cohort of 2,065 insured patients with type 2 diabetes who were newly started on hypoglycemic therapy and were followed for at least 3 years between 1992 and 2001. Medication adherence was assessed by taking the ratio of medication days dispensed (from pharmacy records) to medication days prescribed (as documented in the medical record) for the first prescribed hypoglycemic drug. Adherence was measured for the period between medication initiation and the next elevated A1C result measured at least 3 months later; intensification was defined as a dose increase or the addition of a second hypoglycemic agent.

RESULTS

Patients were aged (mean +/- SD) 55.4 +/- 12.2 years; 53% were men, and 19% were black. Baseline medication adherence was 79.8 +/- 19.3%. Patients in the lowest quartile of adherence were significantly less likely to have their regimens increased within 12 months of their first elevated A1C compared with patients in the highest quartile (27 vs. 37%, respectively, with increased regimens if A1C is elevated, P < 0.001). In multivariate models adjusting for patient demographic and treatment factors, patients in the highest adherence quartile had 53% greater odds of medication intensification after an elevated A1C (95% CI 1.11-1.93, P = 0.01).

CONCLUSIONS

Among insured diabetic patients with elevated A1C, level of medication adherence predicted subsequent medication intensification. Poor patient self-management behavior increases therapeutic clinical inertia.

Cost-related medication nonadherence among elderly and disabled medicare beneficiaries: a national survey 1 year before the medicare drug benefit

BACKGROUND

Prior to implementation of the Medicare drug benefit, we estimated the prevalence of cost-related medication nonadherence (CRN) among Medicare enrollees, including elderly and nonelderly disabled beneficiaries.

METHODS

In the fall of 2004, detailed measures of CRN (skipping or reducing doses or not filling prescriptions because of cost) were added to the Medicare Current Beneficiary Survey. We examined the prevalence of CRN nationally and by Medicare eligibility subgroups (elderly vs nonelderly disabled beneficiaries), drug coverage status, socioeconomic status, self-rated health, and number of chronic medical conditions.

RESULTS

In a national sample of 13 835 noninstitutionalized Medicare enrollees, 29% of the disabled and 13% of the elderly beneficiaries reported CRN; those in fair to poor health with multiple comorbidities and without coverage were most at risk. Among the disabled enrollees with 4 or more morbidities, 52% (95% confidence interval [CI], 43.3%-60.3%) without drug coverage skipped prescriptions or doses compared with 26% (95% CI, 17.7%-34.8%) with Medicaid drug coverage. Those with partial drug coverage through Medigap policies or Medicare health maintenance organizations reported intermediate rates of CRN. The adjusted odds ratio of CRN among disabled enrollees in poor (vs good) health was 3.9 (95% CI, 1.7-9.2), whereas for those with 4 or more (vs <4) comorbidities, the odds ratio of CRN was 2.7 (95% CI, 1.7-4.1).

CONCLUSIONS

One year before Medicare Part D implementation, Medicare beneficiaries reported high rates of CRN. Rates are highest among nonelderly disabled beneficiaries, but among both elderly and disabled beneficiaries, CRN is exacerbated by poor health, multiple morbidities, and limited drug coverage. Given the high cost sharing under Part D, it is important to closely monitor CRN in high-risk subgroups.

Racial differences in impact of coverage on diabetes self-monitoring in a health maintenance organization

BACKGROUND

Insurance coverage of patient self-management devices like self-monitoring blood glucose (SMBG) equipment may help to reduce race-related barriers to effective care.

OBJECTIVES

We examined whether providing free home glucose monitors had greater impacts on self-monitoring among black versus white patients with diabetes.

RESEARCH DESIGN

Using electronic medical record data (1992-1996), we used longitudinal survival analysis to examine racial differences in rates of initiation of SMBG after coverage and rates of discontinuation of SMBG 18 months after initiation. We used piecewise Cox models to compare relative rates of SMBG initiation between black and white patients before and after the policy.

SUBJECTS

The study cohort included 2275 continuously enrolled adult patients with diabetes in a large, staff model HMO. Multivariate models were restricted to patients using oral therapy.

RESULTS

Controlling for time-dependent and fixed effects, black patients were as likely to initiate SMBG as white patients before the policy (hazard ratio 1.14; 95% confidence interval 0.86-1.50) but more likely after the policy (hazard ratio 1.33; 95% confidence interval 1.01-1.76). Among postpolicy SMBG initiators, black patients were consistently at higher risk of SMBG discontinuation than white patients over time (P < 0.05). By the end of follow-up, discontinuation rates were 78% among black patients and 64% among white patients.

CONCLUSIONS

The policy is effective in triggering additional diabetes patients to self-manage, particularly black patients. However, persistence after initiation of monitoring is short-lived. Although our results show the potential of such policies to narrow racial gaps in self-management among racial minority groups, further interventions may be needed to promote long-term adherence.

Physician alerts to increase antidepressant adherence: fax or fiction?

BACKGROUND

Many managed care organizations use feedback based on electronically maintained claims data to alert physicians to potential treatment problems, including patient medication nonadherence. However, the efficacy of such interventions for improving adherence among patients treated for depression is unknown.

METHODS

We examined an antidepressant compliance program consisting of faxed alerts to physicians beginning May 2003 using interrupted time series analysis to evaluate its impact on rates of antidepressant adherence between May 2002 and May 2004 among members of the managed care plan of Harvard Pilgrim Health Care, which is a health plan operating in 3 states in New England, with corporate headquarters in Wellesley, Mass. The program alerted prescribing physicians to patients with gaps of more than 10 days in refilling antidepressant prescriptions during the first 180 days of treatment. Our outcome measures were rates of nonadherence among patients with refill gaps of more than 10 days ("delayed refill") and proportion of days without treatment within the first 180 days of treatment.

RESULTS

A total of 13 128 patients (> or = 18 years of age) who were starting treatment with antidepressants met the study criteria. Rates of nonadherence among patients with delayed refills remained constant (P = .22) over the 2-year study period, averaging 75% (95% confidence interval, 72.7%-77.3%). Rates of antidepressant nonadherence significantly increased over time (P = .04), with an average of 40% (95% confidence interval, 38.4%-41.6%) of days without dispensed antidepressants available during treatment episodes.

CONCLUSIONS

Using real-time pharmacy information to alert physicians regarding patient adherence was not successful in increasing antidepressant adherence rates among members of the managed care plan. Effectiveness of electronically triggered, patient-specific, faxed feedback should be carefully evaluated before widespread implementation, because faxes are insufficient as a stand-alone policy tool.

Race differences in long-term diabetes management in an HMO

OBJECTIVE

We examined race differences in diabetes outcomes over 4-8 years in a single HMO.

RESEARCH DESIGN AND METHODS

We identified black and white adult diabetic patients who were continuously enrolled (1992-2001) and in whom diabetes was 1) diagnosed before 1994 (n = 1,686) or 2) newly diagnosed in 1994-1997 (n = 1,280). We used hierarchical models to estimate the effect of race on average annual HbA(1c) (A1C) controlling for baseline A1C, BMI, and age, as well as annual measures of type of diabetes medications, diabetes-related hospitalization, time and the number of A1C tests, physician visits, and nondiabetes medications. Stratifying by sex accounted for significant interactions between sex and race.

RESULTS

At baseline, black and white patients had similar rates of A1C testing and physician visits, but blacks had higher unadjusted A1C values. In multivariate models, among patients with previously diagnosed diabetes, average A1C was nonsignificantly 0.11 higher (95% CI -0.12 to 0.34) in black than in white men but was 0.30 higher (0.14-0.46; P = 0.0007) in black than in white women. Among patients with newly diagnosed diabetes, the adjusted black-white gap was 0.49 among men (0.17-0.80; P = 0.007) and was 0.05 among women (-0.20 to -0.31), which was positive but not significant.

CONCLUSIONS

Factors other than the quality of care may explain persistent race differences in A1C in this setting. Future interventions should target normalization of A1C by identifying potential psychosocial barriers to therapy intensification among patients and clinicians and development of culturally appropriate interventions to aid patients in successful self-management.

Effect of switching antipsychotics on antiparkinsonian medication use in schizophrenia: population-based study

BACKGROUND

The extent to which atypical antipsychotics have a lower incidence of extrapyramidal symptoms than typical antipsychotics has not been well-evaluated in community practice.

AIMS

To examine the effects of switching antipsychotics on antiparkinsonian medication use among individuals with schizophrenia in UK general practices.

METHOD

We included those switched from typical to atypical antipsychotics (n=209) or from one typical antipsychotic to another (n=261) from 1994 to 1998.

RESULTS

Antiparkinsonian drug prescribing dropped by 9.2% after switching to atypical antipsychotics (P<0.0001). Switching to olanzapine decreased the rate by 19.2% (P<0.0001), but switching to risperidone had no impact. After switching from one typical antipsychotic to another, antiparkinsonian drug prescribing increased by 12.9% (P<0.0001).

CONCLUSIONS

Reduction in antiparkinsonian medication use after switching to atypical antipsychotics was substantial in community practice but not as large as in randomised controlled trials. The rate of reduction varied according to the type of medication.

Does antidepressant adherence have an effect on glycemic control among diabetic antidepressant users?

OBJECTIVE

To examine the relationship between adherence to antidepressant medications and HbA1c levels among patients with diabetes in a managed care setting.

METHOD

The analysis included measures of HbA1c levels before, during, and after initial antidepressant use among 568 patients with diabetes enrolled in the Harvard Pilgrim Health Care insurance plan from 1991-1995. Adherence was defined as four refills in a six-month period after the first antidepressant prescription. General linear models using SAS PROC MIXED were used to estimate the effects of covariates including antidepressant adherence on HbA1c levels over time, comparing patients who were adherent to antidepressant medications to those patients who were non-adherent to antidepressant medications.

RESULTS

Adherence to antidepressant treatment was not significantly associated with HbA1c levels among diabetic patients who are antidepressant users. Younger age, use of insulin and oral medications, and female gender were all significantly associated with HbA1c levels over time.

CONCLUSIONS

Although we did not observe any association between level of adherence to antidepressant therapy among diabetic patients and levels of glucose control, our results confirm previously established associations between patient characteristics and glycemic control. Further research is needed to disentangle the complex relationship among antidepressant treatment adherence and diabetes outcomes.

Antibiotic use following a Korean national policy to prohibit medication dispensing by physicians

This study investigated whether a Korean national policy prohibiting doctors from dispensing drugs as of 2000 selectively reduced inappropriate antibiotic prescribing in viral illness compared with bacterial illness. We assessed the proportions of episodes prescribed an antibiotic and the number of different antibiotics prescribed for patients with viral and bacterial illness episodes before and after the policy. The nationally representative sample consisted of 50,999 episodes (18,656 viral and 7758 bacterial pre-policy, 16,736 viral and 7849 bacterial post-policy) from 1372 primary care clinics. We used generalized estimating equations to investigate changes in antibiotic prescribing after the policy, and multiple linear regression to determine provider factors associated with reductions in inappropriate antibiotic prescribing for viral illness. After the dispensing restriction, antibiotic prescribing declined substantially for patients with viral illness (from 80.8 to 72.8%, relative risk (RR) = 0.89, [95% confidence interval: 0.86, 0.91], p<0.001), and only minimally for patients with bacterial illness (from 91.6 to 89.7%, RR = 0.98, [0.97, 0.99], p = 0.017). Reductions in antibiotic prescribing were significantly larger (RR = 0.90, [0.87, 0.93], p<0.001) for patients with viral illness. The number of different antibiotics prescribed per episode also decreased significantly after the policy, but there were no significant differences in these reductions between viral and bacterial illness. The dispensing restriction also reduced prescribing of non-antibiotic drugs, with no difference by diagnosis. Provider factors found to be associated with reduced inappropriate antibiotic prescribing were younger age and practice location in an urban area. Prohibiting doctors from dispensing drugs reduced prescribing overall, both of antibiotics and other drugs, and selectively reduced inappropriate antibiotic prescribing in viral illness.

Barriers to self-monitoring of blood glucose among adults with diabetes in an HMO: a cross sectional study

BACKGROUND

Recent studies suggest that patients at greatest risk for diabetes complications are least likely to self-monitor blood glucose. However, these studies rely on self-reports of monitoring, an unreliable measure of actual behavior. The purpose of the current study was to examine the relationship between patient characteristics and self-monitoring in a large health maintenance organization (HMO) using test strips as objective measures of self-monitoring practice.

METHODS

This cross-sectional study included 4,565 continuously enrolled adult managed care patients in eastern Massachusetts with diabetes. Any self-monitoring was defined as filling at least one prescription for self-monitoring test strips during the study period (10/1/92-9/30/93). Regular SMBG among test strip users was defined as testing an average of once per day for those using insulin and every other day for those using oral sulfonylureas only. Measures of health status, demographic data, and neighborhood socioeconomic status were obtained from automated medical records and 1990 census tract data.

RESULTS

In multivariate analyses, lower neighborhood socioeconomic status, older age, fewer HbA1c tests, and fewer physician visits were associated with lower rates of self-monitoring. Obesity and fewer comorbidities were also associated with lower rates of self-monitoring among insulin-managed patients, while black race and high glycemic level (HbA1c>10) were associated with less frequent monitoring. For patients taking oral sulfonylureas, higher dose of diabetes medications was associated with initiation of self-monitoring and HbA1c lab testing was associated with more frequent testing.

CONCLUSIONS

Managed care organizations may face the greatest challenges in changing the self-monitoring behavior of patients at greatest risk for poor health outcomes (i.e., the elderly, minorities, and people living in low socioeconomic status neighborhoods).

Supplemental insurance and use of effective cardiovascular drugs among elderly medicare beneficiaries with coronary heart disease

CONTEXT

Cost-sharing in US prescription drug coverage plans for elderly persons varies widely. Evaluation of prescription drug use among elderly persons by type of health insurance could provide useful information for designing a Medicare drug program.

OBJECTIVE

To determine use of effective cardiovascular drugs among elderly persons with coronary heart disease (CHD) by type of health insurance.

DESIGN, SETTING, AND PATIENTS

Cross-sectional evaluation of 1908 community-dwelling adults, aged 66 years or older, with a history of CHD or myocardial infarction from the 1997 Medicare Current Beneficiary Survey, a nationally representative sample of Medicare beneficiaries.

MAIN OUTCOME MEASURES

Use of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins), beta-blockers, and nitrates, and out-of-pocket expenditures for prescription drugs, stratified by type of health insurance: Medicare without drug coverage (Medicare only or self-purchased supplemental insurance) or with drug coverage (Medicaid, other public program, Medigap, health maintenance organization, or employer-sponsored plan).

RESULTS

Statin use ranged from 4.1% in Medicare patients with no drug coverage to 27.4% in patients with employer-sponsored drug coverage (P<.001). Less variation between these 2 types occurred for beta-blockers (20.7% vs 36.1%; P =.003) and nitrates (20.4% vs 38.0%; P =.005). In multivariate analyses, statin use remained significantly lower for patients with Medicare only (odds ratio [OR], 0.16; 95% confidence interval [CI], 0.05-0.49) and beta-blocker use was lower for Medicaid patients (OR, 0.55; 95% CI, 0.34-0.88) vs those with employer-sponsored coverage. Nitrate use occurred less frequently in persons lacking drug coverage (patients with Medicare only, P =.049; patients with supplemental insurance without drug coverage, P =.03). Patients with Medicare only spent a much larger fraction of income on prescription drugs compared with those with employer-sponsored drug coverage (7.9% vs 1.7%; adjusted P<.001).

CONCLUSION

Elderly Medicare beneficiaries with CHD who lack drug coverage have disproportionately large drug expenditures and lower use rates of statins, a class of relatively expensive drugs that improve survival.

The case for a medicare drug coverage benefit: a critical review of the empirical evidence

The lack of an outpatient prescription drug benefit under Medicare has become a conspicuous omission in the face of accelerated growth in prescription drug expenditures and increased availability of highly effective medications. This article provides a critical review of the empirical evidence on the effect of drug coverage on the use of prescription drugs, health care outcomes, and health care costs among Medicare beneficiaries. The existing literature provides considerable evidence that drug coverage is associated with greater use of all drugs and clinically essential medications and that not all forms of coverage provide the same protection. Longitudinal evidence from elderly and disabled persons in Medicaid indicates that restricting coverage has serious adverse health outcomes for sick and low-income beneficiaries that actually lead to increased health care costs.

Use of antihypertensive drugs by Medicare enrollees: does type of drug coverage matter?

Research has demonstrated that Medicare beneficiaries with drug coverage consume more clinically essential drugs. However, generosity of coverage varies considerably across beneficiaries. This study examines the association between types of drug coverage and the consumption and cost per tablet of essential antihypertensive medications among beneficiaries with hypertension. The findings indicate that while both state- and employer-sponsored drug coverage are associated with greater consumption of antihypertensive drugs and lower out-of-pocket costs per tablet, private supplemental coverage is not associated with greater use and is associated with only slightly lower out-of-pocket costs than among noncovered beneficiaries.

Application of the vestibular disorders activities of daily living scale

OBJECTIVE

Existing scales of functional performance are either insufficiently sensitive or omit some important daily life tasks. This paper demonstrates that a new scale of self-perceived disablement in the vestibularly impaired population-the Vestibular Disorders Activities of Daily Living Scale (VADL)-differentiates between disabled and healthy persons and evaluates the associations of this assessment with other measures of vestibular disorders.

STUDY DESIGN

Prospective.

METHODS

Subjects were 1) asymptomatic, healthy adults, 2) patients with benign paroxysmal positional vertigo, 3) patients with chronic vestibulopathy excluding Meniere's disease, postsurgical vertigo, and postconcussion vertigo, and 4) family members. Patient were assessed on the VADL, the Dizziness Handicap Inventory, level of vertigo, and computerized dynamic posturography. Healthy subjects and family members completed the VADL.

RESULTS

The VADL differentiates healthy persons from patients but does not differentiate between patient groups. Patients perceived themselves as more independent than their spouses perceived them to be. Scores are weakly correlated with vertigo frequency and posturography scores for conditions with unreliable kinesthesia and absent or unreliable vision. The VADL is more responsive to higher levels of impairment than the Dizziness Handicap Inventory.

CONCLUSIONS

This well-normed, self-administered scale of self-perceived disablement is useful for evaluating the functional status of patients with peripheral vestibular disorders. Perceptions of patients and significant others vary, but scores are moderately correlated with some standard measures of vestibular function. As it assesses a different domain of function than do standard diagnostic tests, the VADL will augment these tests during initial evaluation and may be useful for assessing posttreatment change.

Evidence of self-report bias in assessing adherence to guidelines

OBJECTIVE

To assess trends in the use of self-report measures in research on adherence to practice guidelines since 1980, and to determine the impact of response bias on the validity of self-reports as measures of quality of care.

METHODS

We conducted a MEDLINE search using defined search terms for the period 1980 to 1996. Included studies evaluated the adherence of clinicians to practice guidelines, official policies, or other evidence-based recommendations. Among studies containing both self-report (e.g. interviews) and objective measures of adherence (e.g. medical records), we compared self-reported and objective adherence rates (measured as per cent adherence). Evidence of response bias was defined as self-reported adherence significantly exceeding the objective measure at the 5% level.

RESULTS

We identified 326 studies of guideline adherence. The use of self-report measures of adherence increased from 18% of studies in 1980 to 41% of studies in 1985. Of the 10 studies that used both self-report and objective measures, eight supported the existence of response bias in all self-reported measures. In 87% of 37 comparisons, self-reported adherence rates exceeded the objective rates, resulting in a median over-estimation of adherence of 27% (absolute difference).

CONCLUSIONS

Although self-reports may provide information regarding clinicians' knowledge of guideline recommendations, they are subject to bias and should not be used as the sole measure of guideline adherence.

An exploratory study of arm-reach reaction time and eye-hand coordination

The study examined the time taken to reach and touch keys positioned both within and just outside the traditional reach envelope, as well as within and just outside the region of easy visibility, defined as being within a 30 degrees cone centered on the line of sight. Movements were required from a start key positioned in front of the subject to a response key positioned at one of 140 positions, defined by seven heights (from 360 to 1080 mm above the seat reference point (SRP), five angles (in vertical planes positioned from 30 degrees across the body to 90 degrees ipsilaterally) and four radii (from 200 mm closer to the body than the normal reach boundary to 100 mm further away than the normal reach boundary). The time taken was divided into detection time (the time from illumination of response signal to release of start key), and movement time (the time from release of start key to contact with response key). Results suggested that the visual cone should be extended downwards, as detection time increased rapidly to keys positioned outside the visual cone upwards, but not in the downwards direction. In general, responses to keys positioned anywhere that was both within the reach envelope and also within the visual cone took approximately the same time, from 371 to 420 ms. Movement time increased with distance moved, but disproportionately so, up to 595 ms, when movement was required to positions that were at one or more of the extremes of height, angle or radius.

Automatic teller machines and the older population

Subjects aged 50 years or older who had never used an automatic teller machine (ATM) were trained to use an ATM manufactured by NCR. There were four groups of 20 subjects. In all groups the training ended with a brief demonstration. Group 1 received the demonstration alone. Group 2 received a flash-card based training task which taught the meaning of the ATM keys. Group 3 received a simulator-based task which taught the idea of pressing buttons sequentially in order to complete a task unrelated to ATMs. Group 4 received all conditions. Results indicated that the demonstration alone was unsuccessful but that there were significant gains from both of the active training tasks. Results from a questionnaire suggested that, for the better performers, the training task also increased motivation to use an ATM. The implications of the results for a practical training task are discussed.

Conspicuity in realistic scenes: an eye-movement measure

An experiment is described to measure the distracting effects of advertisements on the conspicuity of routing signs in realistic scenes. Slides of railway station scenes were shown in which subjects had to search for a target word used in a routing sign present in the scene. Eye movements were recorded to determine search time and number of fixations during search time. Both search time and number of fixations increased systematically with the number of advertisements in two of the three experimental scenes. The distribution of fixations over the scenes is discussed.

Control of cardiac response under aversive stimulation. Superiority of a heart-rate feedback condition

The relative heart rate effects of biofeedback training, deep muscle relaxation, and a no-feedback/music procedure were compared during two criterion situations. The first consisted of a 25-min training period during which subjects received the assigned treatments. The second consisted of the pre- to posttraining reductions in heart rate reactivity to a series of aversive tone-shock trials. On the first criterion, the heart rate decreases of the feedback and no-feedback/music groups were not clearly distinguishable; however, both groups fell significantly below the muscle-relaxation group. By contrast, on the second criterion, the three groups were clearly distinguishable, with feedback subjects evidencing the most heart rate "control", followed by the muscle-relaxation and no-feedback/music groups, respectively. On the segment of the posttraining aversive trials conducted in the absence of the feedback signal, transfer of heart rate control was incomplete for feedback subjects, but still remained below the level of the other two groups. Training effects were more pronounced on tonic than on phasic heart rate changes. The difference between the two criterion situations suggests the possible need for and feasibility of employing a situational arousal methodology in evaluating the extent and limitation of physiological training procedures.