Title: Impact of state mandatory insurance coverage on the use of diabetes preventive care

Transcription

1 Author's response to reviews Title: Impact of state mandatory insurance coverage on the use of diabetes preventive care Authors: Rui Li Ping Zhang Lawrence Barker DeKeely Hartsfield Version: 3 Date: 17 March 2010 Author's response to reviews: see over

2 March 16 th, 2010 Dear Ms. Pafitis, Dr. Laugesen, and Dr. Nelson, Thank you very much for your thoughtful comments on our manuscript, Impact of State Mandatory Insurance Coverage on the Use of Diabetes Preventive Care. We have revised the manuscript based on your comments. In the following, we describe the responses in detail. Thank you for your time. I look forward to hearing from you. Sincerely, Rui Li, M.D., Ph.D. Division of Diabetes Translation National Center of Chronic Disease Prevention and Health Promotion Centers for Disease Control and Prevention 4770 Buford Highway NE, MS-K10 Atlanta, GA, Phone: Fax:

3 Responses to comments: Associate Editor's comments: I think this is an excellent and potentially important article. It deals with an interesting and important issue, conducts strong analyses and is generally clearly written. I do recommend minor revisions, however, and ask the authors to consider the comments provided by the two reviewers. I also suggest that they have someone carefully copy edit the manuscript before resubmitting; it had a number of small grammatical errors (e.g., confusion between "effect" and "affect", use of non-words like "ethnical", etc.). The copy editor should look at the manuscript, figures and tables. Response: a professional editor copy edited the text of the manuscript, tables, and figures before we resubmit the manuscript. As the authors state, this is -- to my knowledge -- the first study to show that mandated diabetes benefits in private insurance lead to improved diabetes behaviors in the form of self monitoring of blood glucose (SMBG), although the effects are modest. I think the authors may actually be a little too modest in discussing the significance of their findings. As they note, many private insurers probably already covered diabetes supplies and many privately insured may be exempt from state mandates because the firms are self-insured. Thus, to find even small overall changes in SMBG suggests that the effects are more potent among those insured by companies that did not previously cover diabetes supplies, but did so after the mandates kicked in. From a policy perspective, the significance of these findings is also larger than the authors note. Some argue that we should reduce insurance mandates and one common Congressional proposal is to permit the interstate sale of insurance policies, which could effectively undercut the effect of individual states' insurance mandates. For example, Sen. Enzi (ranking Republican in the Senate HELP Committee) has periodically proposed such legislation. This article indicates the public health significance of state insurance mandates for one of the most prevalent and harmful chronic diseases. In addition to considering the comments from the two reviewers, I would suggest the authors make three clarifications: (1) Since state mandates for diabetes may vary, how did they define when a state had mandates and when it did not, since mandates are classified as a dichotomous variable. That is, if a state mandates one aspect of diabetes (e.g., must cover insulin) but not another (e.g., coverage of needles or testing strips), how did they decide if there is a mandate or not? Response: on page 7, under State Mandates Variables, the first paragraph, line 6, we added We did not distinguish among states by contents of mandated coverage, since almost all states legislation mandated DSME and diabetes equipment and supplies.

4 (2) Table 3 indicates they used state fixed effects, but the methods section does not say this. The methods section should say so. Response: on page 7, under Covariates, the first sentence, we wrote We considered both state and individual-level covariates. State covariates included: a state fixed effect to control for the state time-invariant characteristics;. (3) Since many in the biomedical community are more used to seeing odds ratios to present logistic regression model effects, it might be helpful to parenthetically compute the four key results (daily SMBG, annual eye exam, annual foot exam and all three) in terms of odds ratios also. They can leave their main discussion in terms of marginal predicted probabilities, but some will understand odds ratios better. Response: on page 10, the last paragraph, the first sentence, we wrote Table 3 shows the predicted marginal probabilities and odds ratios of the legal variables and control variables on the use of diabetes preventive care measures considered. In Table 3, we reported odds ratios and its 95% confidence intervals below the marginal probabilities. Let me reflect on a couple of the reviewers' comments: I thought Dr. Laugesen's comments on the impact of mandates on providers was interesting and worth adding. Response: We added it to page 13, the second paragraph, starting at line 4 One possible explanation is that annual eye and foot exams, unlike SMBG, require more effort from health providers than from the patients, and state mandates do not directly affect providers practice pattern, although the mandates reduced the burden of filing paperwork claiming authorization. I don't agree with Dr. Nelson's statement about the lack of evidence that SMBG impacts outcomes. This is still broadly viewed as one of the most important goals of self-management of diabetes and remains a Healthy People objective. Contrary to Dr. Nelson, I thought paragraph 2 on page 13 was worthwhile, although it could be reworded to be a little clearer. Response: on page 13, the last paragraph, we rewrote the paragraph: Direct (mandating benefit coverage) and indirect (the effect achieved through increased knowledge obtained via DSME) effects could not be isolated, and our data did not allow us to determine whether the expanded DSME coverage actually resulted in an increase in patients taking DSME classes. All but one of the states that passed mandates between 1997 and 1999 covered DSME. DSME classes often include material concerning the importance of performing SMBG and receiving annual eye and foot exams to prevent diabetic complications. i Prior to the mandates being passed, coverage of DSME was unusual. For example, a study in 1994 reported that only 35.1% of the US adult population with diabetes attended any diabetes classes or programs, primarily due to lack of reimbursement ii,iii. However, our results suggest that the effects of DSME classes during the study period might be limited. This could be due to how the mandates on DSME were

5 implemented: many mandates included restrictions on who should receive the benefits and who could be reimbursed for providing DSME. Thus the benefits of mandated coverage on DSME might not be realized in the initial years after the mandates passed. All in all, I think this is an excellent article and I hope the authors work on it promptly, so it can be published soon. Reviewer 1 s comments Reviewer: Miriam Laugesen Reviewer's report: Thank you for giving me the opportunity to read this paper. I like it and recommend it be published with minor revisions. There really is very little empirical work on the impact or cost of mandated benefits. One reason is that the few studies we have show very little effect. However, the authors do a really nice job of showing how there might be small changes and there are benefits to adopting these policies; and potentially how the mandated benefits may enhance the effect of quality guidelines or interact with them. Minor revisions there seems to be dip in 1998 in the charts for non-mandated states -- this is uniform and interesting. It is worth commenting on. Response: on page 10, the first paragraph, line 5, we rewrote The rates of patients performing SMBG and receiving eye and foot exams increased in both those states enacted mandates and those not having mandates except in In that year, there was a dip in the charts for all nonmandate states, while in states with mandates, the slopes were all positive. P marginal probability for eye exams is not statistically significant. Response: We added not significant in the parenthesis. There might be data on the self-insured firm prevalence (p 12) from the Kaiser Family Foundation survey. p 13 explain the point that mandates don't impact providers --- I would have thought they do; it removes the hassle in claiming authorization -- although I guess there is probably no insurance company that would deny that benefit in the absence of a mandate. Basically you might want to acknowledge the paperwork hassles that mandates remove. Response: yes, We added it to page 13, the second paragraph, starting at line 4 One possible explanation is that annual eye and foot exams, unlike SMBG, require more effort from health providers than from the patients, and state mandates do not directly affect providers practice pattern, although the mandates reduced the burden of filing paperwork claiming authorization. I don't know if diabetes care is included in the preventive benefits under health

6 care reform but you might want to check it. Response: from American Diabetes Association website, diabetes care is included in the preventive benefits under health care reform. On page 7, the last two sentences, we added Following the same rationale, if the new health care reform covering preventive care proposed by President Obama passed iv, an increase in the use of diabetes preventive care among uninsured people with diabetes is plausible v. These people, now not covered by insurance, might receive coverage for preventive care. The authors could argue that the increase in the rates of utilization, while small, over time that adds up to a lot more utilization. Response: on page 16, line 6, we added In addition, small increases in rate of utilization, over time, can add up. Since we do not know what happened after our study ended, it is possible that the small increase in performing daily SMBG that we detected might, eventually, have a positive impact on public health. The last sentence of the conclusion needs a bit of work; lots of states already analyze impacts. So maybe make it stronger. Response: we changed it to If the purpose of state mandates is to provide improved benefits to many persons, state policy makers in states that do not do so should determine the number of people a mandate would benefit prior to passing the mandate. Reviewer 2 s comments Reviewer's report Reviewer: Karin Nelson Reviewer's report: Major Revisions: The manuscript entitled "Impact of State Mandatory Insurance Coverage on the Use of Diabetes Preventive Care" deals with the question that is of interest, namely do state mandates for care improve diabetes care? The authors found small effects from the passage of mandates for services. While this is an interesting finding, I m not sure they can conclude their results weren t from other programs (e.g., report cards, quality improvement initiatives) that occurred over the same time period. This point needs to be clarified in the discussion section. Response: in the method, we controlled for time trends, which could control the effects of national programs. However, if the programs differed in different states, our results might be confounded.. In the limitation session on page 15, second paragraph, line 7, we added Fifth, although we used time trend to control the effect of national programs such as NCQA report cards and other diabetes quality improvement initiatives, if the effects of these programs differed among the states, our results might be confounded. In the limitations, there should also be discussion about the increasing lack of evidence that SMBG actually impacts outcomes, so this area may not be as of

7 much interest as in the past. For statistical review: Comment on the interpretation of the marginal probabilities. Are insulin users really 40% more likely to perform daily SMBG or is this the predicted probability that they perform this task? Response: they were predicted probabilities. We explained it in the parenthesis following the numbers. Minor issues that should be addressed: Conclusion Had our data sources allowed us to restrict our analyses to those whose employers were subject to state mandates, we would probably have found larger effects is speculative and not supported by data. Is there another citation that suggests this is true? Response: on page 13, paragraph 1, the last sentence, we rewrote the sentence and added reference 21 Considering the larger size of the effect of similar mandates in the Medicare population,, we would probably have found larger effects here had our data sources allowed us to restrict our analyses to those whose employers were subject to state mandates. First sentence of the second full paragraph on page 13 The size of the indirect effect. is unclear. Response: on page 13, paragraph 3, the sentence was changed to Direct (mandating benefit coverage) and indirect (the effect achieved through increased knowledge obtained via DSME) effects could not be isolated, and our data did not allow us to determine whether the expanded DSME coverage actually resulted in an increase in patients taking DSME classes. Some sentences are not well written and could use editing: o The positive signs of the coefficients page 13. Response: on page 14, the second paragraph, we changed to Members of racial and ethnic minorities and low income persons could plausibly be more likely than others to be underinsured, therefore, they might benefit more from the mandates. When we examined interaction terms between the variables indicating presence of a mandate and the variables indicating membership in these groups, the coefficients of the interaction terms were positive. This suggested that the state mandates might have had more effect on use of the preventive care in people who were underinsured and less likely to have these coverage before the state mandates. o Don t need to define coding scheme for variables (page 7 dichotomous variable (0/1) Response: we deleted (0/1). Is 63% of individuals receiving an eye exam really a ceiling effect? (Page 13). Most quality improvement initiatives have a much higher target.

8 Response: we explained further on page 13, following this sentence Ceiling effects may also play a role: 63% and 59% percent of patients had received annual eye exams and foot exams before the state mandates, respectively, while only 44% performed SMBG daily. The effect of expanding insurance coverage in further increasing the proportion of patients receiving annual eye exams and foot exams might be limited. Other strategies might be considered. Consider deleting paragraph 2 on page 13 beginning with The size of the indirect effect of state mandatory coverage on performing SMBG. Response: on page 13, the last paragraph, we rewrote the whole paragraph Direct (mandating benefit coverage) and indirect (the effect achieved through increased knowledge obtained via DSME) effects could not be isolated, and our data did not allow us to determine whether the expanded DSME coverage actually resulted in an increase in patients taking DSME classes. All but one of the states that passed mandates between 1997 and 1999 covered DSME. DSME classes often include material concerning the importance of performing SMBG and receiving annual eye and foot exams to prevent diabetic complications. vi Prior to the mandates being passed, coverage of DSME was unusual. For example, a study in 1994 reported that only 35.1% of the US adult population with diabetes attended any diabetes classes or programs, primarily due to lack of reimbursement vii,viii. However, our results suggest that the effects of DSME classes during the study period might be limited. This could be due to how the mandates on DSME were implemented: some mandates included restrictions on who should receive the benefits and who could be reimbursed for providing DSME. i The statement These mandates may have contributed to the expansion of Medicare s coverage. is speculative and not supported by the data presented. Response: we added a reference: reference 7. Given that annual eye and foot exams are largely driven by providers, I would delete the sentence many people have not availed themselves of annual eye and foot exams. Response: on page 16, line13, we changed to On the other hand, our results show that, although the employer or the insurers have already provided the preventive benefits for people with diabetes, many people have not received them. Thank you very much for your interest and help! Best regards, Rui Li, Ph.D.

9 Senior Service Fellow and Health Economist Division of Diabetes Translation Centers for Disease Control and Prevention Phone: Fax: