Title: Assessing socioeconomic health care utilization inequity in Israel: Impact of alternative approaches to morbidity adjustment

Transcription

1 Author's response to reviews Title: Assessing socioeconomic health care utilization inequity in Israel: Impact of alternative approaches to morbidity adjustment Authors: Efrat Shadmi Ran D Balicer (rbalicer@clalit.org.il) Karen Kinder (kkinder@jhsph.edu) Chad Abrams (cabrams@jhsph.edu) Jonathan P Weiner (jweiner@jhsph.edu) Version: 2 Date: 1 June 2011 Author's response to reviews: see over

2 Dear Editor, June 1, 2011 We thank the editors and reviewers for their comments and suggestions for the improvement of the manuscript. Below is our detailed response to each of the comments. Reviewer: Lyn Sibley Major Compulsory Revisions 1. In the absence of a gold standard the expected relationship between SES and utilization for each type of health services needs to be clearly stated and supported by the literature We thank the reviewer for this comment and added a description of the literature on the direction of the association between SES and health care use. Studies from other developed countries have demonstrated that persons of low economic status utilize less specialist services than their more affluent counterparts [5-8], yet findings on pro-rich specialty care use also exist [9]. Primary care is generally shown to be equitably distributed in universal coverage health care systems [6, 10], however inequitable primary care use is also reported [11]. These inconsistent findings may reflect actual variations in patterns of SES and health care use, yet they may be a result of differences in measurement of health needs [12]. 2 a. How are diagnosis codes collected/recorded. It is suggested that diagnosis data is obtained from electronic medical records. Are these EMRs maintained in physicians offices or a central location? Are diagnosis codes collected as a part of billing? Details on collection of diagnoses codes were added to the end of the methods section.

3 Diagnoses are routinely electronically recorded during all medical encounters for clinical and care management (non-billing) purposes, and are then stored in a central data warehouse. 2 b. How are the distributions of ACGs in the three datasets compared using Pearson s r. Following comment number 7 (minor revisions) we removed analyses that used the ACG groupings and conducted all analyses using ADGs. This is now reported both in the methods and the results sections accordingly. Pearsons' rs are now reported for the ADG comparisons. The overall distribution of ADGs in Clalit was very similar to that of the US and the Spanish samples (Pearson r = 0.89, and 0.95 respectively). 2 c. How was the CCI applied? The CCI on data on chronic conditions registered in Clalit's Chronic Disease Registry (CCDR). An explanation regarding the CCI was added to the methods section. Data on chronic conditions were obtained from the Clalit's Chronic Disease Registry (CCDR), which aligns information from electronic medical records of physician visits and hospitalizations, as well as data on prescription drugs and information from diagnostic and lab tests. The registry's classification is verified by individual physicians, that request changes in their patients' chronic illness status in cases of misclassification [28]. 3 d. Were the ADGs included in the model as dummy variables? Yes, ADGs were added as dummy variables. This is now reported in the methods section. 3. Results - Descriptive information A table was added with information on age, gender, the Charlson index, ADGs and social security waiver entitlement for the entire sample and for the sub sample of adult

4 enrollees. Additionally, the CCI distribution is further delineated in the beginning of the results section. Due to restrictions in disclosing financial information we do not report distribution of health care resource use. Relative use (percent of enrollees in each SES group with above average resource use in each of the categories) is provided in table 2. The average CCI score for the total sample and for the adults sub-sample was 1.2 and 1.6, respectively (range in each group 0-22). About 60% of all enrolees (and about 50% of all adults) had a CCI score of zero. Minor Essential Revisions 4. Background - The reference regarding the relationship between socioeconomic status and health is 30 years old We thank the reviewer for this comment and have now added more updated references 5. Background - More information about the Israeli health care system would be helpful to the reader Details on the Israeli health care system and insurance coverage were added to the background In Israel, all residents are covered by mandatory health insurance, financed mainly by a progressive health tax, and provided by one of four health funds, operating as insurers and providers. Clalit Health Services is the largest (non-for-profit) health fund in Israel, with over 3.9 million enrolees (53% market share), operating services distributed throughout Israel, including 1500 primary and secondary care clinics, 14 hospitals, labs and diagnostic imaging facilities. Clalit members receive, at the point of care, free primary care and hospitalization services. Specialty care and imaging services incur a copayment. Persons of low SES (who receive social security entitlements) receive a complete or partial waiver for these copayments, depending on their social security entitlement status. Despite universal coverage and copayment

5 waivers, previous Israeli studies have shown that disadvantaged groups face more barriers to specialty care than the rest of the population [3,4]. 6. Methods - The G in ADG stands for group This was corrected throughout the manuscript 7. Methods - If ADGs (and not ACGs) are being evaluated in the anaysis, then why compare the distribution of ACGs (and not ADGs) with distributions from other countries? This was corrected, as stated above and the comparison is now reported for ADGs rather than ACGs. 8. Methods -, the ACG system components Thank you for point out this discrepancy. This mistake was corrected. Discretionary Revisions 9. Background - I suggest that the second to last paragraph be expanded by adding a sentence of two stating more specifically what this study is contributing to the literature As stated above, the second paragraph was revised. Additionally, we rephrased the aim of the study to better clarify what this study aims to add to the literature The aim of this study was to examine the degree to which adjustment for morbidity using a diagnoses-based morbidity measure based on tools of the Johns Hopkins University Adjusted Clinical Groups (ACGs) [19-22], explains differences in health care use by socioeconomic status, better than other commonly used health needs measures

6 10. Methods - Those who died or were born in the study year were excluded from the sample The sample actually did include persons who were born or died during This is now clearly stated in the methods. A representative sample of about 10% of all members of Clalit during the entire year of 2009, including persons born or those who have died during the year, was selected. 11. Methods If the ADGs are used in the analysis and the ACGs are not, it is unnecessary and confusing to describe the ACGs The description of ACGs was removed. 12. Methods - The number of days in hospital is a more informative indicator of hospital utilization We agree with the reviewer that hospital days may be more informative than whether an hospitalization occurred or not. Yet, we believe that issues related to accessibility of services may affect hospitalization events rather than length of stay. For example, persons who utilize less community imaging services may be admitted to the hospital for performance of emergency tests that could have been prevented. 13. Table 2 should have the N for the sample as well as the average (cut point)for physician visits and diagnostic tests As noted above actual use data is restricted 14. It would be easier to compare unadjusted odds ratios with the adjusted odds ratios than comparing the percentages with adjusted odds ratios We thank the reviewer for this comment, yet we feel it is unlikely that no adjustment for health need is performed and that at the minimum age and gender is accounted for, therefore we feel that providing unadjusted estimates may confuse the reader.

7 Reviewer: Hengjin Dong Actually from the background information, it is very hard to say this because so far there is no information about the health fund, Clalit Health Services. Do enrollees have co-payment while using services? If yes, do thy the same for different health care services? Do the adults with social security waiver get 100% free services? We thank the reviewer for this comment and have now added information on Clalit Health Services and on the waiver entitlement in the Background section. In Israel, all residents are covered by mandatory health insurance, financed mainly by a progressive health tax, and provided by one of four health funds, operating as insurers and providers. Clalit Health Services is the largest (non-for-profit) health fund in Israel, with over 3.9 million enrolees (53% market share), operating services distributed throughout Israel, including 1500 primary and secondary care clinics, 14 hospitals, labs and diagnostic imaging facilities. Clalit members receive, at the point of care, free primary care and hospitalization services. Specialty care and imaging services incur a copayment. Persons of low SES (who receive social security entitlements) receive a complete or partial waiver for these copayments, depending on their social security entitlement status. Despite universal coverage and copayment waivers, previous Israeli studies have shown that disadvantaged groups face more barriers to specialty care than the rest of the population [3,4]. They should very clear explain why the persons of low SES cannot have higher utilization of specialists and diagnostic services. We thank the reviewer for these suggestions and have incorporated possible explanations os the findings in the discussion.

8 A possible explanation for the inequitable use of health services reported here is that, as reported also by others, persons of low SES face non-financial barriers to health service use [2,3]. These barriers may include poorer availability of services, cultural and language gaps that may affect minorities, who constitute large percentages of low SES populations, or differences in preferences. Future research is required to test whether differences in use reflect the level of needed care by persons from diverse SES groups (i.e., whether underutilization or overutilization exists) and to assess the degree to which inequity reduction programs succeed in minimizing unwarranted gaps. Another suggestion is to make the sentence shorter so that the readers can follow the text easier. Grammar needs check We appreciate this comment and have rechecked the paper for grammatical errors. Sincerely, Efrat Shadmi (on behalf of the research team) Efrat Shadmi PhD, RN Faculty of Welfare and Health Sciences University of Haifa Mount Carmel, Haifa 31905, Israel Office: Fax.: