Improving Asthma Treatment in a Managed Care Population

, ,
The American Journal of Managed Care, June 2005, Volume 11, Issue 6

Objective: To identify and educate members of ConnectiCare,Inc & Affiliates, a regional managed care organization, who werenot using asthma medications as recommended by the NationalHeart, Lung, and Blood Institute, by means of a nurse-administered6-month telephonic case management intervention called theAsthma Treatment Awareness Project.

Study Design: A randomized controlled design was used toevaluate intervention and control groups. Self-selected memberswho opted in, opted out, or did not respond to an invitation to participatewere included in the analysis.

Methods: Changes in asthma medication use, physician officevisits, emergency department visits, hospitalizations, and quality oflife were measured. A change in asthma medication use was measuredusing an asthma medication index ranging from 0 to 1.00,with a higher score indicating a better prescribing pattern.

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Results: There was significant improvement in asthma medicationuse for all groups, but the asthma medication index increaseof 0.176 for the intervention group was nearly 2 times the 0.091increase for the control group. This difference remained significant(= .04) after using analysis of variance to control for age and thepreintervention asthma medication index. There was also a significantincrease in overall quality of life for the intervention group(= .04) but not for the control group.

Conclusion: Individualized telephonic case management froma specially trained registered nurse may be effective in improvingasthma medication use and quality of life in subjects that do notuse asthma medications according to National Heart, Lung, andBlood Institute guidelines.

(Am J Manag Care. 2005;11:361-368)

Asthma prevalence in the United States has beensteadily increasing. From 1980 to 1996, asthmaprevalence increased by 74%.1 Asthma ranksamong the most common chronic conditions in theUnited States, affecting an estimated 16 million adults,or 7.5% of the US population, and causing more than470 000 hospitalizations and nearly 5000 deaths ayear.1,2 The National Heart, Lung, and Blood Institute(NHLBI) estimates that the economic burden of asthmais $14.0 billion in direct ($9.4 billion) and indirect ($4.6billion) costs.3

Although asthma is a chronic condition, it remainstreatable and amenable to self-management education.Asthma can be managed through "trigger" avoidanceand medication therapy in accord with recognizedtreatment guidelines.4 The NHLBI created asthmaguidelines to improve quality of care and patient outcomes.The guidelines call for a stepwise approach toasthma management, recommending inhaled corticosteroidsas the most effective method for controllingpersistent asthma.

Nationally, physicians are increasingly more likely totreat their patients with asthma according to NHLBIbest practices. Stafford and colleagues5 found that theproportion of annual total asthma visits for which aninhaled corticosteroid was prescribed increased from8% from 1978 to 1988 to 48% in 2002. Although the prescribingof inhaled corticosteroids has increased substantially,at least 1 study6 reports that as many as 64%of users of inhaled corticosteroids underuse the drug.Asthma management programs have been developedto assist with the identification and removal of asthmatriggers, increase anti-inflammatory medication use,decrease short-term rescue medication use, improvequality of life, and decrease medical service utilization.7-9Asthma education delivered in the physician's office,10through interactive multimedia programs11 and asthmaeducation classes,12 is associated with appropriate antiinflammatorymedication use.

The primary limitation of asthma education deliveredthrough a physician's office is that only about halfof adults with asthma routinely visit their physician.13This is especially true for those who have not been prescribedan anti-inflammatory medication or are notusing it as intended. Persons using short-acting rescuemedications may be refilling their prescriptions withouthaving had a recent evaluation by their physician.

As more persons with asthma enroll in managed careorganizations, an opportunity exists to identify personswith the condition and offer self-management educationtelephonically and through printed educational materials.Educational self-management intervention has beenfound to significantly improve adherence with inhaledcorticosteroid therapy and perceived control of asthma.9 Population-based disease management programshave resulted in reduced medical service utilization,8,14,15 improved quality of life,8,15 decreased costs,16and increased anti-inflammatory medication use.14Although telephonic interventions have been describedin association with asthma and other chronic conditions,17,18 none of the identified studies used a nurse-administeredtelephonic intervention tested in arandomized controlled trial.

This article describes the effectiveness of an asthmamanagement program in improving asthma medicationuse in accord with nationally recognized guidelines, inreducing medical service utilization, and in improvingdisease-specific quality of life. A randomized controlleddesign was used to identify study participants. TheAsthma Treatment Awareness Project is an asthmamanagement program that was developed and implementedby ConnectiCare, Inc & Affiliates, a regionalmanaged care organization, as an adjunct to an existingasthma management program called Better RespirationEquals Asthma Treatment and Health Education.

METHODS

ConnectiCare, Inc & AffiliatesAsthma Management Program

International

Classification of Diseases, Ninth Revision,

Clinical Modification

ConnectiCare, Inc & Affiliates is an independentpractice association-model regional managed careorganization with approximately 270 000 members anda network of 14 000 practitioners and 61 hospitals.Members identified as having asthma using the code 493.XX are automaticallyenrolled in the ConnectiCare, Inc & Affiliates BetterRespiration Equals Asthma Treatment and HealthEducation asthma management program. Since the programbegan in 1996, targeted members have periodicallyreceived printed educational materials, an invitationto attend a free asthma education class, and a quarterlycopy of the ConnectiCare, Inc & Affiliates member publication.Physicians are notified quarterly of members'asthma-related emergency department visits, hospitalizations,or inappropriate medication use according toNHLBI guidelines.

Asthma Medications

The Asthma Treatment Awareness Project was addedin 2001 to identify members who were not using asthmamedications as recommended by the NHLBI.19Pharmacy claims data were used to identify memberswho had been dispensed 3 or more short-acting or long-actingβ2-agonist prescriptions for any 3 consecutivemonths in a 12-month period without a correspondingprescription for an anti-inflammatory medication duringthe same 3 consecutive months. Long-acting β2-agonistprescriptions were included even though the NHLBIidentifies long-acting β2-agonists as 1 of several long-termcontrol medications. The guidelines stipulate thatthey should not be used in place of anti-inflammatorytherapy but rather used concomitantly with anti-inflammatorymedication for long-term control of symptoms.19

β2-agonist prescriptions included 1 or more short-actingβ2-agonists (albuterol, albuterol sulfate, pirbuterolacetate, metaproterenol sulfate, or terbutalinesulfate) or a long-acting β2-agonist (albuterol sulfateextended-release tablets or salmetorol xinofoate). Antiinflammatorymedications included inhaled corticosteroids(beclomethasone dipropionate, budesonide,flunisolide, fluticasone propionate, or triamcinoloneacetonide), leukotriene modifier (montelukast sodium,zafirlukast, or zileuton), cromolyn sodium, ornedocromil sodium.

Asthma Medication Index

The asthma medication index is a value that rangesfrom 0 to 1.00, with a higher score indicating a betterprescribing pattern. It is derived by dividing the totalnumber of dispensed anti-inflammatory drug prescriptionsby the sum of dispensed β2-agonist prescriptionsand dispensed anti-inflammatory drug prescriptions.Dispensed prescriptions were identified in rolling 3-month intervals throughout a 12-month period. Anasthma medication index of 0 during any of the 3-month intervals qualified a member for the study. Amember could have an asthma medication indexgreater than 0 during the 12-month period, however, ifthe member was dispensed an anti-inflammatory medicationoutside of the rolling 3-month interval that qualifiedhim or her for the study. The asthma medicationindex has been used in previous studies,20-23 demonstratinga correlation with hospital admissions21 andemergency department visits.23

An asthma medication index of 0.50 or greater indicatesthat for every β2-agonist prescribed there would beat least 1 anti-inflammatory medication prescribed. Theindex would move in the desired direction withdecreases in β2-agonist use or increases in anti-inflammatorymedication use. Members with an index of 0.50or greater were excluded from the study, because theyhad attained a minimum desired index before theintervention. Although opportunities for improvementin asthma management among members with an indexof 0.50 or greater may exist, the intervention wasintended for members who had a less favorable prescribingpattern.

Subjects

Members had been enrolled in ConnectiCare, Inc &Affiliates for at least 3 months before the time of identification.Members were identified quarterly during 1year and then followed up for 12 months after entry intothe study to address seasonal differences in asthmasymptoms. Members 65 years and older were excludedbecause of the prevalence of chronic obstructive pulmonarydisease as a comorbid condition in this agegroup. Those younger than 13 years were excludedfrom the analysis because the asthma quality-of-lifeinstrument used (discussed in the next subsection) wasonly validated for persons 13 years and older.

Study Design

After identification, members were sent a letterdescribing the benefits of using long-term asthma controlmedication if they were using quick-relief asthmamedication 3 or more times per week or waking up atnight with asthma symptoms such as wheezing, coughing,or chest tightness. Members were introduced to theBetter Respiration Equals Asthma Treatment and HealthEducation program and were asked to complete a quality-of-life questionnaire and to indicate their willingnessto receive a telephone call from a nurse case manager.

The 15-item Mini Asthma Quality of Life Questionnaireby Juniper et al24 was used to measure quality oflife at baseline and at the 12-month follow-up, whichwas 6 months after the final telephone contact for thosewho completed the intervention. The Mini AsthmaQuality of Life Questionnaire, developed from the 32-item Asthma Quality of Life Questionnaire, has beenvalidated and has shown good reliability.24

Subjects who responded "probably yes" or "probablyno" to the invitation to be contacted by a nurse casemanager were deemed appropriate for randomizationand were equally likely to be placed in the interventionor control groups. Unrestricted randomization was usedto determine assignment of the first subject, followed byalternating group assignment according to the order inwhich responses were received. Because this study wasconducted with active members of a health plan, definitiverequests were honored. Therefore, those whoresponded "definitely yes" were considered part of anopt-in group and received the intervention, while thosewho responded "definitely no" were considered part ofan opt-out group and did not receive the intervention.These categories remained distinct in the analysis in aneffort to address selection bias. A final category of membersincluded those who did not respond to the initialquestionnaire. Asthma medication use was measuredfor nonresponders as a way to assess the potential fortemporal bias in asthma medication trends during thestudy period.

The asthma nurse case managers were required tohave a registered nurse license from the state ofConnecticut, a minimum of 4 years' clinical experience,and asthma education training from a board-certifiedallergist or pulmonologist and to maintain compliancewith the ConnectiCare, Inc & Affiliates requirementsfor continuing education.

Follow-up reminder telephone calls and questionnaireswere provided to all nonrespondents. Memberswho were randomized to the intervention group or whorequested a telephone call from a nurse case managerwere telephoned for initial assessment within 1 monthafter their questionnaire was received. The nurse thenprovided monthly telephonic self-management educationalsessions for 6 months. The nurse case managerassessed members' knowledge of their disease process,existence of an asthma action plan, awareness ofnationally recognized treatment guidelines, and overalllevel of confidence with managing their asthma.Compliance with medication use, adherence to thephysician-directed asthma management plan, peak flowmonitoring behaviors, and trigger minimization andavoidance were evaluated monthly by obtaining selfreportedinformation from the members during casemanagement telephone contact. The nurse case managerprovided feedback to the members regarding thesebehaviors. In addition, members receiving case managementreceived a packet of educational materials tailoredspecifically to their needs. This packet includedage-specific bilingual printed and video educationalmaterials, as needed, as well as specific asthma managementdevices. A language telephone line fornon-English speakers and a telephone device for thedeaf for members with a hearing impairment were alsoavailable, as needed.

Data Analysis

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The outcome variables included the before and afterasthma medication indexes, physician office visits,emergency department visits, hospitalizations, andquality of life. Statistical Package for the SocialSciences, version 12.0 (SPSS Inc, Chicago, Ill) was usedto conduct &#967;2 tests and Wilcoxon signed rank tests forunivariate analyses, and analysis of variance was usedfor multivariate analyses. Statistical significance wasconsidered at < .05.

A square root transformation was used for skeweddistributions of the preintervention and postintervention asthma medication indexes before multivariateanalysis. Square root transformations were also used forskewed before and after quality-of-life scores. Initialunivariate models included the preintervention variablesand showed significant improvement betweenpreintervention and postintervention variables. The preinterventionvariables were included in the multivariatemodel to account for between-group differences inthe preintervention asthma medication index, as well asthe quality-of-life scores. By testing and rejecting thehypothesis that the preintervention asthma medicationindexes were equal to 1, it was demonstrated that preinterventionindexes were not consistent with postinterventionindexes and that a preintervention index shouldbe used to adjust for the effect of different startingpoints on the preintervention index. A dummy variablewas created for all groups, with the control group servingas the referent group.

RESULTS

Subject Identification and Demographics

There were 836 members who met the identificationcriteria. Of these, 367 members who were not continuouslyenrolled in ConnectiCare, Inc & Affiliates for 24months were excluded. In addition, 39 members whoself-reported that they did not have asthma and 31 whohad an asthma medication index of 0.50 or greater wereexcluded. Members with an asthma medication index of0.50 or greater were considered less likely to be usingtheir asthma medications inappropriately and thuswere not targeted to receive an intervention. Therefore,399 members (48%) were included in the final analysis,including 67 in the intervention group, 67 in the controlgroup, 28 in the opt-in group, 52 in the opt-out group,and 185 who did not return a baseline questionnaire.There were 134 members randomized to the interventionor control groups, for a participation rate of 34%.

Telephone contacts were attempted for all membersin the intervention group and the opt-in group. An initialcontact was made with 81% of the interventiongroup and 89% of the opt-in group. During the initialcontact, members received general information aboutasthma management and were asked to identify a treatmentplan. Some members indicated that they hadobtained all of the information they needed from thisinitial contact and did not want further contacts. A secondcontact was made with 40% of the interventiongroup and 79% of the opt-in group. Four or more contactswere used as an indicator of program completion.Twenty-seven percent of the intervention group and68% of the opt-in group completed the program.

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As presented in Table 1, the 399 members includedin the final analysis were equally divided between male(49%) and female (51%) subjects. The mean age was36.0 years, with two thirds of the members beingyounger than 45 years. Although there was an overalldifference (= .03) among the groups with respect toage, this was only significant for the opt-in group (43.9years) compared with the nonrespondents (34.8 years)(= .02). There was no statistically significant differencein the mean age of the subjects in the intervention(35.0 years), control (36.0 years), or opt-out (37.3years) groups. Forty-one percent of subjects had ananti-inflammatory medication dispensed in the previous12 months, while the entire cohort had a mean of8.1 short-acting &#946;2-agonist prescriptions dispensed.

Asthma Medication Outcomes

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There were significant increases in the asthma medicationindex for all groups (Table 2). The increase of0.285 for the opt-in group was the largest, while the0.091 increase for the control group was the smallest.The 0.176 increase for the intervention group wasnearly 2 times the 0.091 increase for the control group.After using analysis of variance to control for age andthe preintervention asthma medication index, the differencebetween all groups was significant (= .04).Age was entered in the multivariate analysis as a categoricalvariable (13-20, 21-44, 45-64 years). Sex wasremoved as a covariate because it was not a significantpredictor in the model. Compared with the controlgroup, improvements were significant for the interventiongroup (= .04) and the opt-in group (= .01)(Table 3). Age was also a statistically significantpredictor of asthma medication index differences,revealing improvements in the groups aged 21 to 44years (= .001) and 45 to 64 years (= .008) comparedwith the group aged 13 to 20 years. However, there wereno statistically significant differences in the numbers ofphysician office visits, emergency department visits, orhospitalizations.

Quality-of-Life Outcomes

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Quality-of-life differences were measured for allresponding groups (Table 4). There was a statisticallysignificant increase in overall quality of life for the interventiongroup (= .04). The intervention group alsodemonstrated increases in 2 of the 4 subscales, includingemotional function (= .045) and environmentalstimuli (= .04). There were no statistically significantdifferences for the control group, opt-in group, or optoutgroup, nor were there significant between-group differencesin the multivariate analysis.

DISCUSSION

This study provides evidence of improvement inasthma medication use among 5 different groups ofstudy participants. Regardless of randomization orintervention status, the mean asthma medication indexincreased during a 12-month period. The improvementin all groups is consistent with recent studies5,25,26 thatdemonstrate trends in increased use of controller medicationswith concomitant decreased use of short-actingreliever medications. Nevertheless, the largest increaseswere seen in those members who received the intervention,whether randomized or self-selected.

The study revealed that member motivation is animportant factor in determining improvement in asthmamanagement. The opt-in group had the highestproportion of members to complete the program andthe largest asthma medication index increase. Thefindings indicate that members who chose to receivethe intervention achieved better outcomes. Thisstudy highlights the importance of self-motivation asan indicator of readiness to initiate and maintainasthma self-management.

As previously stated, 27% of the intervention group and68% of the opt-in group completed the program. Becausesignificant improvement in the asthma medication indexwas achieved for these 2 groups, they appear to have benefitedfrom receiving a portion of the Asthma TreatmentAwareness Program. A redesignedshorter program may have similarsuccess. It is also likely thatincreased completion rates may leadto improved outcomes.

Improvements in the asthmamedication index were greater inthe older compared with theyounger age groups. This finding isconsistent with other studies6,26that demonstrate the association ofthe underuse of inhaled corticosteroidswith younger age. This maysignal the need for age-appropriateinterventions that target youngerage groups.

A multicontact telephone interventiondelivered by a nurse casemanager was effective in increasingappropriate asthma medication use. Because of the seasonalityof the disease, and to improve adherence withproper medication therapy, ConnectiCare, Inc &Affiliates developed and implemented the 6-monthAsthma Treatment Awareness Project intervention toaccomplish this goal. Others have reported interventionsranging from a single session to multiple sessions duringa 12-month period, with varying levels of success.8

The program demonstrated improvement in asthmamedication use for members in the intervention groupcompared with those in the control group. This wasaccomplished in spite of the low program completionrates. Because subjects mostly had mild-to-moderateintermittent asthma, no hospitalizations in the pastyear, minimal emergency department visits, and highquality-of-life scores at baseline, it is likely that theywere not significantly impaired by their condition. Thiscould have contributed to the low program completionrate. A larger sample would be needed to determine theoptimal level of intervention that would be required toproduce desired changes in medication use, quality oflife, and medical service utilization. A longer observationperiod may have also resulted in greater medicalservice utilization among the control group.

The asthma medication index threshold chosen forinclusion in the study was less than 0.50, because thesesubjects would have the least favorable prescribing patterns.In accord with recommendations in the NHLBIguidelines, members using a short-acting &#946;2-agonistmore than 2 times per week for intermittent asthmamay need to receive long-term control therapy.19 Onceanti-inflammatory medication is initiated and maintained,the asthma medication index is expected toincrease, representing a decrease in &#946;2-agonist use andan increase in anti-inflammatorymedication use. Although anindex of 0.50 does not necessarilyinfer optimal control,increases in the asthma medicationindex across an asthmapopulation indicate improvedchanges in prescribing patternsconsistent with NHLBI guidelines.Asthma medication indexincreases are also likely toresult from member behaviorchanges, including medicationcompliance. The group thatattained the highest postinterventionasthma medicationindex was the opt-in group, at0.382 for a 12-month period.Further research would beneeded to determine the meanasthma medication index for apopulation with asthma.

A limitation of this studywas the use of pharmacy claimsdata as an indicator of actualmedication use. The exclusiveuse of pharmacy claims datamay underestimate actualmedication use by not consideringthe use of samplesreceived from physicians orprescriptions that are coveredby a different pharmacy benefit.As many as 13% of studyparticipants reported receiving at least 1 free sample ofan anti-inflammatory medication from their physician.

Based on an earlier study27 of children with asthma,a poor correlation between self-reported complianceand objectively measured compliance would seem toindicate that pharmacy claims data may underestimateactual medication use. However, a recent study28demonstrated a significant correlation between dailyanti-inflammatory drug intake as estimated by pharmacyrecords and daily anti-inflammatory drug intake asdetermined by inhaler emptying rates, thereby callingthe previous assumption into question.

The lack of sociodemographic, ethnic, and racialinformation limits the generalizability of our results tospecific subgroups. The sample was drawn from a managedcare organization that does not offer services toMedicare or Medicaid beneficiaries, and most subjectsare employed or are dependents of employed healthinsurance subscribers. Previous research has shownthat insured persons are more likely to promptly filltheir prescriptions and take recommended dosages.29Our sample was representative of the employed, mostlywhite, populations of Connecticut and westernMassachusetts. Therefore, the study may overestimatethe use of inhaled corticosteroids for the general population,because underuse of inhaled corticosteroids hasbeen shown to be associated with nonwhite race.6,10

Individualized telephonic case management from aspecially trained registered nurse is an effective wayto provide self-management education to a high-riskgroup with asthma. By identifying persons who arenot using asthma medications as recommended bythe NHLBI, a telephonic intervention such as the onein this study can address basic self-managementissues to yield desired medication adjustments.Extending this research will assist healthcare organizationsin selecting effective programs to treat individualswith asthma.

Acknowledgments

We thank Paul S. Salva, MD, PhD, Jay Salvio, RN, MBA, and BarbaraLangley for their suggestions in the preparation of the manuscript. We alsothank Deborah Dauser, MPH, and Stephen Walsh, ScD, for their assistancewith the statistical analysis.

From Health Management Programs, ConnectiCare, Inc & Affiliates, Farmington,Conn.

This study was funded by ConnectiCare, Inc & Affiliates.

Address correspondence to: Steven Delaronde, MPH, MSW, Health ManagementPrograms, ConnectiCare, Inc & Affiliates, 175 Scott Swamp Road, Farmington, CT 06032.E-mail: sdelaronde@connecticare.com.

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