Robert B. Penfold

Use of Interrupted Time Series Analysis in Evaluating Health Care Quality Improvements

Interrupted time series (ITS) analysis is arguably the strongest quasi-experimental research design. ITS is particularly useful when a randomized trial is infeasible or unethical. The approach usually involves constructing a time series of population-level rates for a particular quality improvement focus (eg, rates of attention-deficit/hyperactivity disorder [ADHD] medication initiation) and testing statistically for a change in the outcome rate in the time periods before and time periods after implementation of a policy/program designed to change the outcome. In parallel, investigators often analyze rates of negative outcomes that might be (unintentionally) affected by the policy/program. We discuss why ITS is a useful tool for quality improvement. Strengths of ITS include the ability to control for secular trends in the data (unlike a 2-period before-and-after t test), ability to evaluate outcomes using population-level data, clear graphical presentation of results, ease of conducting stratified analyses, and ability to evaluate both intended and unintended consequences of interventions. Limitations of ITS include the need for a minimum of 8 time periods before and 8 after an intervention to evaluate changes statistically, difficulty in analyzing the independent impact of separate components of a program that are implemented close together in time, and existence of a suitable control population. Investigators must also be careful not to make individual-level inferences when population-level rates are used to evaluate interventions (though ITS can be used with individual-level data). A brief description of ITS is provided, including a fully implemented (but hypothetical) study of the impact of a program to reduce ADHD medication initiation in children younger than 5 years old and insured by Medicaid in Washington State. An example of the database needed to conduct an ITS is provided, as well as SAS code to implement a difference-in-differences model using preschool-age children in California as a comparison group.

Laboratory and self-report assessments of impulsive behavior in adolescent daily smokers and nonsmokers

This research compared adolescent daily smokers (n=25) and nonsmokers (n=26) on different measures of impulsivity. Assessments included question-based measures of delay (DDQ) and probability (PDQ) discounting, a measure of behavioral disinhibition (go-stop task), and a self-report measure of impulsivity (Barratt Impulsiveness Scale-Adolescent). Adolescent smokers were more impulsive on the DDQ and Barratt Impulsiveness Scale--Adolescent but not on the PDQ or the go-stop task. However, there was a significant interaction between smoking status and gender on the go-stop task, with male smokers performing less impulsively on this measure than male nonsmokers--an effect not observed with the female adolescents. These findings indicate that adolescents who smoke cigarettes are more impulsive with respect to some, but not all, types of impulsivity than are adolescents who do not smoke.

Changes in antidepressant use by young people and suicidal behavior after FDA warnings and media coverage: quasi-experimental study

Objective To investigate if the widely publicized warnings in 2003 from the US Food and Drug Administration about a possible increased risk of suicidality with antidepressant use in young people were associated with changes in antidepressant use, suicide attempts, and completed suicides among young people. Design Quasi-experimental study assessing changes in outcomes after the warnings, controlling for pre-existing trends. Setting Automated healthcare claims data (2000-10) derived from the virtual data warehouse of 11 health plans in the US Mental Health Research Network. Participants Study cohorts included adolescents (around 1.1 million), young adults (around 1.4 million), and adults (around 5 million). Main outcome measures Rates of antidepressant dispensings, psychotropic drug poisonings (a validated proxy for suicide attempts), and completed suicides. Results Trends in antidepressant use and poisonings changed abruptly after the warnings. In the second year after the warnings, relative changes in antidepressant use were −31.0% (95% confidence interval −33.0% to −29.0%) among adolescents, −24.3% (−25.4% to −23.2%) among young adults, and −14.5% (−16.0% to −12.9%) among adults. These reflected absolute reductions of 696, 1216, and 1621 dispensings per 100 000 people among adolescents, young adults, and adults, respectively. Simultaneously, there were significant, relative increases in psychotropic drug poisonings in adolescents (21.7%, 95% confidence interval 4.9% to 38.5%) and young adults (33.7%, 26.9% to 40.4%) but not among adults (5.2%, −6.5% to 16.9%). These reflected absolute increases of 2 and 4 poisonings per 100 000 people among adolescents and young adults, respectively (approximately 77 additional poisonings in our cohort of 2.5 million young people). Completed suicides did not change for any age group. Conclusions Safety warnings about antidepressants and widespread media coverage decreased antidepressant use, and there were simultaneous increases in suicide attempts among young people. It is essential to monitor and reduce possible unintended consequences of FDA warnings and media reporting.

Nurse Navigators in Early Cancer Care: A Randomized, Controlled Trial

PURPOSE To determine whether a nurse navigator intervention improves quality of life and patient experience with care for people recently given a diagnosis of breast, colorectal, or lung cancer. PATIENTS AND METHODS Adults with recently diagnosed primary breast, colorectal, or lung cancer (n = 251) received either enhanced usual care (n = 118) or nurse navigator support for 4 months (n = 133) in a two-group cluster randomized, controlled trial with primary care physicians as the units of randomization. Patient-reported measures included the Functional Assessment of Cancer Therapy-General (FACT-G) Quality of Life scale, three subscales of the Patient Assessment of Chronic Illness Care (PACIC), and selected subscales from a cancer adaptation of the Picker Institutes patient experience survey. Self-report measures were collected at baseline, 4 months, and 12 months. Automated administrative data were used to assess time to treatment and total health care costs. RESULTS There were no significant differences between groups in FACT-G scores. Nurse navigator patients reported significantly higher scores on the PACIC and reported significantly fewer problems with care, especially psychosocial care, care coordination, and information, as measured by the Picker instrument. Cumulative costs after diagnosis did not differ significantly between groups, but lung cancer costs were

Antipsychotic Medication Use Among Children and Risk of Diabetes Mellitus

6,852 less among nurse navigator patients. CONCLUSION Compared with enhanced usual care, nurse navigator support for patients with cancer early in their course improves patient experience and reduces problems in care, but did not differentially affect quality of life.

Health care use and decision making among lower-income families in high-deductible health plans.

OBJECTIVE: To assess whether the risk of incident diabetes was increased with the use of second-generation antipsychotics (SGAs) in a large diverse cohort of children. METHODS: A retrospective study was conducted by using the administrative databases of 3 health plans participating in the Health Maintenance Organization Research Network. Children 5 to 18 years of age who initiated SGA therapy between January 2001 and December 2008 and 2 comparison groups, namely, nonusers of psychotropic drugs and users of antidepressant medications, were identified. Diagnoses from inpatient and outpatient records, pharmacy dispensings, and outpatient laboratory results were used to identify incident cases of diabetes. RESULTS: The crude incidence rate of diabetes for the SGA-exposed cohort was 3.23 cases per 1000 person-years (95% confidence interval [CI]: 1.67–5.65), compared with 0.76 cases per 1000 person-years (95% CI: 0.49–1.12) among nonusers of psychotropic medications and 1.86 cases per 1000 person-years (95% CI: 1.12–2.90) among antidepressant users. The risk of incident diabetes was significantly increased among SGA users (unadjusted incidence rate ratio: 4.24 [95% CI: 1.95–8.72]) in comparison with nonusers of psychotropic medications but was not significantly increased in comparison with antidepressant medication users (unadjusted incidence rate ratio: 1.74 [95% CI: 0.77–3.78]). CONCLUSIONS: Although we found a potentially fourfold increased rate of diabetes among children exposed to SGAs, the findings were inconsistent and depended on the comparison group and the outcome definition.

Use of antipsychotic medications in pediatric populations: what do the data say?

BACKGROUND Lower-income families may face unique challenges in high-deductible health plans (HDHPs). METHODS We administered a cross-sectional survey to a stratified random sample of families in a New England health plans HDHP with at least

Identification of Stevens-Johnson syndrome and toxic epidermal necrolysis in electronic health record databases.

500 in annualized out-of-pocket expenditures. Lower-income families were defined as having incomes that were less than 300% of the federal poverty level. Primary outcomes were cost-related delayed or foregone care, difficulty understanding plans, unexpected costs, information-seeking, and likelihood of families asking their physician about hypothetical recommended services subject to the plan deductible. Multivariate logistic regression was used to control for potential confounders of associations between income group and primary outcomes. RESULTS Lower-income families (n = 141) were more likely than higher-income families (n = 273) to report cost-related delayed or foregone care (57% vs 42%; adjusted odds ratio [AOR], 1.81; 95% confidence interval [CI], 1.15-2.83]). There were no differences in plan understanding, unexpected costs, or information-seeking by income. Lower-income families were more likely than others to say they would ask their physician about a

Pediatric Uptake of a Newly Available Antipsychotic Medication

100 blood test (79% vs 63%; AOR, 1.97; 95% CI, 1.18-3.28) or a

Screening for Behavioral Health Issues in Children Enrolled in Massachusetts Medicaid

1000 screening colonoscopy (89% vs 80%; AOR, 2.04; 95% CI, 1.06-3.93) subject to the plan deductible. CONCLUSIONS Lower-income families with out-of-pocket expenditures in an HDHP were more likely than higher-income families to report cost-related delayed or foregone care but did not report more difficulty understanding or using their plans, and might be more likely to question services requiring out-of-pocket expenditures. Policymakers and physicians should consider focused monitoring and benefit design modifications to support lower-income families in HDHPs.