Associations of timing, level, and pattern of secondhand smoke exposure with early alcohol initiation: A cohort study.

BACKGROUND: Few studies explored the longitudinal link between early-life secondhand smoke (SHS) exposure and later alcohol initiation despite its risk for child behavioral difficulties. We examined the associations of the timing, level, and pattern of SHS exposure from pregnancy to childhood with early alcohol initiation and evaluated the sex differences in these associations. METHODS: Data were from 16,440 participants of the Taiwan Birth Cohort Study conducted when the children were aged 6 months, 18 months, 3 years, 5.5 years, 8 years, and 12 years. Group-based trajectory modeling was applied to identified patterns of SHS exposure. A series of multiple logistic regression were conducted to examine study hypotheses. RESULTS: Exposure to prenatal SHS was associated with an increased risk of early alcohol initiation (adjusted odds ratio [aOR] = 1.17, 95% confidence interval [CI] = 1.06, 1.30). Compared with the adolescents with a persistent-low-exposure trajectory, those who exhibited prenatal-high-decreasing (aOR = 1.18, 95% CI = 1.04, 1.35) or persistent-high-exposure (aOR = 1.27, 95% CI = 1.12, 1.45) patterns exhibited increased risks of early alcohol initiation. Those with higher cumulative levels of SHS exposure also exhibited an increased risk of early alcohol initiation (aOR = 1.03, 95% CI = 1.01, 1.04). Sex differences were also observed. CONCLUSIONS: Varying timing, levels, and longitudinal patterns of SHS exposure during early life had differential effects on early alcohol initiation, with the effects differing by sex. Targeting SHS exposure while considering the nature of exposure and sex differences could help prevent and curb alcohol use in adolescents.

Trade agreements and tobacco control policy: analysis of the impact of FCTC on regulatory contents of trade agreements from 2001 to 2019.

BACKGROUND: This study aims to analyze the impact of Framework of Convention of Tobacco Control (FCTC) on regulatory contents of trade agreements from 2001 to 2019. METHODS: A search of trade agreements from'WTO Regional Free Trade Agreement Database' using keywords including "tobacco", "cigarette", "smoking" and "FCTC" from May to August 2020 resulted in a total sample of 268 trade agreements, from which 69 trade agreements were coded and analyzed. Provisions in trade agreements, identified via the aforementioned keywords, were categorized into 6 trade measures. The word counts of the provisions containing; FCTC; were calculated. Chi-square tests were applied to analyze the differences of regulatory patterns between different time frames. The import and export values (USD) of tobacco products under trade agreements containing the term "FCTC" were further collected from the "International Trade Statistics 2001-2020" for understanding the impact of the provision on the trade flow. RESULTS: Among 69 agreements, the percentage of trade agreements containing keyword as "FCTC" increased significantly from 0% to 2011 to 12% after 2011. A significant decrease of using trade measures as "the exclusion list" was found after 2011 (from 10% to 0). The word counts of provisions containing; FCTC; increased from 24 words in 2011 to 164 words in 2018, and the content of the provisions became more concrete over time. There are six trade agreements containing "FCTC", and all these 6 agreements were ratified by European Union (EU). Despite EU ratified trade agreements with "FCTC", the import and export values of tobacco products between EU and the other party countries increased with time. But the gap of average trade values between trade agreements with and without "FCTC" being widened with time. CONCLUSIONS: As a first study evaluated the impact of FCTC on regulatory contents of trade agreements, our study results showed that after countries signed trade agreements containing keyword FCTC, the regulatory contents changed significantly. Further studies are recommended to understand the reason and criteria for incorporating FCTC provisions into trade agreements, especially in the EU.

Family environment characteristics and sleep duration in children: Maternal mental health as a mediator.

BACKGROUND: Family environment is a key factor affecting children's health. However, little is known about whether and how the family environment affects sleep duration in children. This study investigated the effects of both physical and social characteristics of the family environment on sleep duration in children and determined whether these associations were mediated by maternal mental health. METHODS: Data were obtained from the Taiwan Birth Cohort Study. A total of 19,400 children who completed 6-month, 18-month, 3-year, 5.5-year, and 8-year surveys were analyzed. The physical family environment characteristics were household crowding and housing quality. Family functioning was used as an indicator of family social environment. Multiple linear regression and path analysis were performed to test the hypotheses. RESULTS: The children living in crowded households had shorter sleep durations (ß = -0.03, p < .001). Superior housing quality and family functioning were associated with longer sleep durations (ß = 0.04 and 0.02, respectively, ps < .01). The effects of housing quality and family functioning on sleep duration were mediated by maternal mental health. CONCLUSIONS: Both physical and social characteristics of the family environment are critical to sleep duration in children. The effects of family environment characteristics on sleep duration in children are in part mediated by maternal mental health. Interventions to improve sleep during childhood by targeting the family environment may be more effective when maternal mental health is considered.

The mediating effect of dietary patterns on the association between mother's education level and the physical aggression of five-year-old children: a population-based cohort study.

BACKGROUND: Relatively few studies have investigated the effects of diet on behavior problems among preschoolers, particularly, physical aggression. In addition, children raised by poorly educated mothers usually have a higher probability of developing negative outcomes. Additionally, highly educated mothers have a higher probability of providing more healthy foods for their children. Thus, mothers providing healthy foods might mitigate children's behavior problems. The study aims to examine whether preschoolers' dietary pattern, as a manipulable factor, mediates the association between maternal education level and physical aggression. METHODS: Data came from the Taiwan Birth Cohort Study (TBCS), a nationally representative population-based cohort study, which included 18,513 five-year-old Taiwanese children. Mothers and primary caregivers reported the information on preschoolers' physical aggression and food consumption at age 5 and maternal education level at age 6 months. Two dietary patterns, namely a healthy diet and a high-fat-sugar-salt (HFSS) diet, were retrieved by exploratory factor analysis. Mediation hypotheses were tested by a series of multiple regression models conducted using the PROCESS macro of SAS 9.4. All models were adjusted for children's sex, parental marital status, household income, mental distress at age 5 and children's physical aggression at age 3. RESULTS: Maternal education positively linked to healthy dietary patterns (B = 0.014, p = 0.002) which was negatively associated with preschoolers' physical aggression (B = -0.096, p = 0.013), and it is negatively related to the HFSS dietary pattern (B = -0.042, p = 0.002) which was directly positively associated with preschoolers' physical aggression (B = 0.123, p = 0.008). The association between maternal education and preschoolers' physical aggression was partially mediated by preschoolers' healthy (B = -0.001, p < .001) and HFSS (B = -0.005, p = <.001) dietary patterns, respectively. The R-square of the mediation model is 0.178. CONCLUSIONS: Preschoolers' dietary patterns directly associate with their physical aggression. In addition, mothers with poor education may provide less healthy foods and more unhealthy foods to their children, which may increase the level of physical aggression. The results imply partial mediating effects of dietary patterns between maternal education and physical aggression. It is suggested that a parent-based nutritional education program focusing on healthy meal preparation for poor educated mothers might be beneficial for preschoolers' healthy development.

Risk factors for asthma occurrence in children with early-onset atopic dermatitis: An 8-year follow-up study.

BACKGROUND: Children with early-onset atopic dermatitis (AD) are at substantial risk of developing asthma later in life, and identifying the critical window of detrimental exposure is advantageous for implementing preventive actions. The aim of this study was to evaluate the role of exposure to environmental modifiers during pregnancy and early childhood in asthma occurrence in an infantile AD cohort. METHODS: Eligible study participants were selected from the Taiwan Birth Cohort Study, which enrolled 24 200 newborns in 2005. We enrolled those cases who had been diagnosed as having AD before 3 years of age and followed them up till age 8. We excluded those ever diagnosed with asthma before AD onset. The dependent variable was defined in terms of whether the participant was diagnosed as having asthma before 8 years of age. We applied logistic regression models to evaluate the risks of exposure to different determinants in asthma occurrence. RESULTS: A total of 1549 children with AD had completed the 8-year follow-up, and 334 (21.6%) of them had asthma. The results revealed that male sex, lower birth order, maternal asthma history, maternal obesity before pregnancy, and environmental tobacco smoke exposure before 3 years of age were significant risk factors for further development of asthma. Furthermore, food allergy during early life, lower respiratory tract infection, and longer durations of symptomatic AD influenced asthma development later in life. CONCLUSIONS: The findings confirmed the critical determinants for asthma occurrence in infantile AD, which may enable a more personalized approach to the prevention of asthma.

Developing an adequate supply of health services: Taiwan's path to Universal Health Coverage.

Universal Health Coverage (UHC) calls for universal effective coverage, which emphasizes that people must have reasonably equal access to covered services. A critical question then arises: what policies can a nation adopt to assure an adequate supply of services and distribute them reasonably to each community and socioeconomic strata? Taiwan relied on incentives, public and private partnership and effective regulations to produce the adequate supply for UHC and distributed them. Taiwan's experience holds a valuable lesson for other nations. Taiwan was the last state in the 20th century to achieve UHC when it implemented the National Health Insurance (NHI) program in 1995. Political timing was crucial in the government's decision to achieve UHC, but the key to its success in providing effective coverage to its 23 million population was the readiness of the health service sector, the result of two decades of planning and development in the pre-NHI period. This paper analyzes how Taiwan historically built up the supply of health services that made achieving UHC possible. We identified four key strategies adopted in the health service sector development, namely: 1) enhancing public-private partnerships in developing medical resources with tax incentives and subsidies; 2) ameliorating regional disparities in medical resource distribution through incentives and effective regulation; 3) safeguarding quality of care by regulating providers through licensing and accreditation programs; and 4) promoting an evidence-based policy-making process.

In utero and early childhood exposure to secondhand smoke in Taiwan: a population-based birth cohort study.

OBJECTIVES: This study provides secondhand smoke (SHS) exposure data in utero and after birth when children were at 18 months, 36 months and 66 months old, and it identifies risk factors for the early childhood SHS among 18-month-old infants living in smoker and non-smoker households. STUDY DESIGN: The data come from the Taiwan Birth Cohort Study, a longitudinal survey of a birth cohort born in 2005. This study used the survey wave when children were 18 months old (n=18 845) for statistical analysis of early childhood SHS exposure. Logistic regression was used to identify the risk factors of the SHS exposure. RESULTS: Approximately 62% of the 18-month-old infants lived in a household with at least one smoker, with the father being the smoker in 84% of those households. Among these infants living in a smoker household, 70% were exposed to SHS and 36% were exposed to heavy SHS in utero, and the prevalence was approximately 66% and 17% after birth for SHS and heavy SHS, respectively. The number and the existence of smokers in the household, parents' smoking status, father's educational attainment and being a first-born baby are strong predictors of early childhood heavy SHS exposure. CONCLUSIONS: Encouraging families to have a smoke-free home environment, empowering women to ensure their perspectives and rights are embedded into tobacco control efforts and educating families about the health risks from childhood SHS exposure, especially among people living in households with smokers, will protect non-smoking adults and children from SHS exposure.

Urban and Education Disparity for Autism Spectrum Disorders in Taiwan Birth Cohort Study.

This study aimed to determine the optimal cut-off for autism spectrum disorder (ASD) screening in 66-month-old children, and to explore the distribution of ASD screening and diagnosis in Taiwan. The Taiwan Birth Cohort Study dataset was used (N = 20,095). The Modified Checklist for Autism in Toddlers (M-CHAT) cut-off point of 13/14 was considered optimal for screening of children at 66 months. More children were diagnosed with ASD in urban areas. Parents of children diagnosed with ASD had a higher level of education, but parents of children with a lower level of education were screened as being at higher risk of ASD. Urban disparity and parental level of education effected parental awareness of the illness and the rate of ASD diagnosis.

Healthy living practices in families and child health in Taiwan.

OBJECTIVES: The aim of this study was to examine the hypothesis that inexpensive and feasible healthy living practices in families, particularly in disadvantaged families, can promote the health of children. METHODS: The dataset was obtained from the Taiwan Birth Cohort Study and comprises a nationally representative sample of 19,712 3-year-old children in Taiwan. The Child Healthy Living Practices in Families (CHLPF) Index, which rates various items of personal hygiene, vegetable and fruit consumption, physical activity, time spent viewing television, and exposure to smoking, was created, and a logistic regression analysis was conducted to test the hypothesis. RESULTS: Higher CHLPF levels were significantly and consistently associated with better child health in families of all income levels. More specifically, the prevalence of ill health in children from poor families with a high CHLPF level was actually lower than that in children from affluent families with a low CHLPF level. CONCLUSIONS: The implementation of low-cost and practical healthy living practices in families can effectively improve child health, especially that of disadvantaged children.

The association between relative deprivation and self-rated health, depressive symptoms, and smoking behavior in Taiwan.

Relative deprivation has been hypothesized as one explanation for the association between income inequality and health. However, few studies have examined the effect of relative deprivation on psychosocial and behavioral outcomes. Using a cross-sectional data from the National Survey on Knowledge, Attitude, and Practice of Health Promotion in Taiwan, this study examined the relationship between relative deprivation and physical health (self-rated health), psychosocial health (depressive symptoms), and behavioral health (smoking) among working-age Taiwanese men and women. We found that higher relative deprivation (measured by the Yitzhaki Index) is significantly associated with a higher prevalence of poor self-rated health, depressive symptoms, and current smoking in both genders. After controlling for demographic variables and absolute income, the prevalence ratios (PRs) of reporting poor health for each 10,000 NT-dollars higher in the Yitzhaki Index are between 1.25 and 1.57, depending on the reference groups. The PRs were between 1.33 and 1.77 for depressive symptoms, and between 1.04 and 1.46 for smoking. Additionally, the depressive symptoms attenuated the association between relative deprivation and self-rated health. The results were consistent with various definitions of reference groups. In conclusion, this study suggests that the psychosocial process of relative deprivation is a crucial mechanism linking income inequality to health. Narrowing the income gap between rich and poor may protect the physical and mental well-being of the population and reduce the prevalence of smoking.

Hospital competition and inpatient services efficiency in Taiwan: a longitudinal study.

There is no consistent evidence of the relationship between market competition and hospital efficiency. Some studies indicated that more competition led to a faster patient turnover rate, higher hospital costs, and lower hospital efficiency. Since the 1980s some studies found market competition could increase the efficiency of inpatient services. However, there were few studies testing the market competition during a hospital's earlier stages on its efficiency during later stages, or the dynamic of efficiency. In this study, we examined the effect of early-stage market competition on later-stage hospital efficiency in Taiwan, and we determine the efficiency change using longitudinal study design. The data for the analysis came from the annual national hospital survey of 1996 and 2001 provided by the Department of Health. There were 102 teaching hospital be analysed. The results show that no evidence supports the proposition that higher market competition would improve the efficiency of hospitals in delivering inpatient services in Taiwan. Importantly, neither was the inefficiency score nor the Malmquist productivity index of inpatient services associated with the level of hospital market competition, regardless of the adjustment for hospital characteristics. However, the results may be related with the hospital increasing beds investment behavior.

Developing and refining the Taiwan Birth Cohort Study (TBCS): five years of experience.

The Taiwan Birth Cohort Study (TBCS) is the first nationwide birth cohort database in Asia designed to establish national norms of children's development. Several challenges during database development and data analysis were identified. Challenges include sampling methods, instrument development and statistical approach to missing data. The purpose of this paper is to describe the pilot study underpinning the TBCS, testing of the TBCS developmental instrument and the resolution of methodological challenges. Bayesian analysis fill in missing data, three-step regression analysis for the investigation of mediating and moderating effect, the use of structural equation modeling in a large scale investigation, investigating direct and indirect effects, confounding factors and reciprocal relationships in children's development, and used latent growth model in longitudinal observations are described. The TBCS will provide ongoing longitudinal information regarding the predisposing and maintaining factors affecting the long term outcome of pediatric illnesses.

Evolution of Taiwan's health care system.

This study aims to present an overview of the evolutionary policy process in reforming the health care system in Taiwan, through dissecting the forces of knowledge, social-cultural context, economic resources and political system. We further identify factors, which had a significant impact on health care reform policies in Taiwan through illustrative policy examples. One of the most illuminating examples highlighted is the design and implementation of a single-payer National Health Insurance (NHI) program in 1995, after nearly five years of planning efforts (1988-1993) and a two-year legislative marathon. The NHI is one of the most popular social programs ever undertaken in the history of Taiwan, which greatly enhances financial protection against unexpected medical expenses and assures access to health services. Nonetheless, health care reform still has an unfinished agenda. Despite high satisfaction ratings, Taiwan's health care system today is encountering mounting pressure for new reforms as a result of its rapidly aging population, economic stagnation, and imbalanced NHI checkbook. Although there may exist some heterogeneous system characteristics and challenges among different health care systems around the world, Taiwan's experiences in reforming its health care system for the past few decades may provide valuable lessons for countries going through rapid economic and political transition.

Parental concerns based general developmental screening tool and autism risk: the Taiwan National Birth cohort study.

Early detection of developmental delay and childhood disorders are important for early intervention. This study aimed to describe the distribution of responses in a large population-based survey, identify cutoff points for the parent concern checklist (PCC) suitable for the Chinese language and culture, and explore how many children were identified as having evidence of problems at age 18 mo different from those at age 6 mo. Using a national randomly selected sample, the overall development of 21,248 children was investigated using the Taiwan Birth Cohort study instrument, and the PCC, a problem-oriented screening instrument. The Newton-Raphson iteration showed that the PCC should be separated into three groups, those scoring 1-2 in the first group, 3- 6 in the second group, and 7- 8 in the third group.Structural equation models showed that 6-mo development was predictive of 18-mo development; additionally, 18-mo development and the PCC showed good concurrent validity. This study identified three groups with distinct developmental trajectories and two cutoff points of 2/3 and 6/7. Thus, the PCC can be used as a first-stage screening instrument in a two-stage window screening procedure. Further studies are needed to investigate the factors, which contribute to the differences among these groups;follow-up on the typical and atypical development of these children is necessary.

Depressive symptoms, smoking, and cigarette price elasticity: results from a population-based survey in Taiwan.

OBJECTIVES: To understand the association between depressive symptoms and smoking. In addition, we investigate how smokers with and without depressive symptoms may respond to cigarette price change differently. METHODS: We used data drawn from a nationally representative survey in Taiwan. Totally, 13,030 male adults were included in the analysis. Depressive symptoms were measured using the Taiwanese depression questionnaire. A logistic regression model was estimated to examine the odds ratio of smoking for those with depressive symptoms versus those without depressive symptoms. Focused on smokers, the ordinary least squares multivariate regression method was used to estimate the cigarette price elasticity. RESULTS: Compared to those without depressive symptoms, those with depressive symptoms were more likely to smoke (44.5 vs. 50.1%) and consume more cigarettes per day (18.4 vs. 21.0). The odds ratio of smoking for those with depressive symptoms, adjusted for demographic variables, was 1.3 (95% confidence interval, 1.1-1.6). The cigarette price elasticity was estimated at -0.82 and -0.41 for depressive smokers and non-depressive smokers, respectively. CONCLUSIONS: Although the association between depression and smoking had been documented, this study contributes to previous literature by investigating the extent to which cigarette price elasticities may differ between smokers with and without depressive symptoms. Results indicate that depressive smokers are more sensitive to the change of cigarette price. Therefore, tax/price increases can also be a very effective means of tobacco control for depressive smokers.

Efficient developmental screening instrument for 6- and 18-month-old children in the Taiwan Birth Cohort Pilot Study.

AIM: To develop an efficient developmental screening instrument for interview purposes. METHODS: Using random sampling, two groups of babies were selected: The pilot group of 1747 babies was selected for testing of reliability and validity. Another group of 100 babies was selected for testing of the concurrent validity with the second edition of the Bayley Scale of Infant Development. The Taiwan Birth Cohort Study scales include four developmental dimensions: gross motor, fine motor, language/communication (language) and social/self-care ability (social). RESULTS: In testing the concurrent validity, the structural equation model showed that Taiwan Birth Cohort Study dimensions correlated with the Bayley Scale of Infant Development dimensions. In testing the predictive validity of the Taiwan Birth Cohort Study, the correlation between the 6- and 18-month results of the motor index was 0.29, and the language social index was 0.31. CONCLUSION: The Taiwan Birth Cohort Study 6- and 18-month scales fulfill the criteria of developmental norm, predictive validity, validity and identification of relative risk for screening instruments. As a self-report checklist, it is economical and efficient, thus, it can be utilized in clinical and community settings.

Development of a risk-adjusted capitation model based on principal inpatient diagnoses in Taiwan.

BACKGROUND AND PURPOSE: Taiwan's National Health Insurance (NHI) program has considered the use of capitation payments to health care providers as a method for control of the rising costs of the system. The establishment of capitation payments usually requires the performance of risk adjustment. The purposes of this study were to develop a diagnosis-based risk adjustment model for the NHI and to evaluate its predictability. METHODS: Using a 2% random sample of 371,620 NHI enrollees, the authors developed a Taiwan version of the Principal Inpatient Diagnosis Cost Groups (TPIPDCGs) from 1996 claim records to predict an individual's expenditure in 1997. Weighted least squares regression models were built in an estimation sample (two-thirds of the study sample), and were cross-validated in a validation sample (the remaining one-third of the study sample). Predictive R2 and predictive ratios were used to evaluate the model's predictability. RESULTS: Only 7.88% of the study sample could be classified into 1 of the 16 TPIPDCGs. Combined with demographic variables, which alone could explain 3.7% of the variation in an individual's future expenditure, the risk adjustment model based on TPIPDCGs could explain 12.2% of expenditure variation. In addition, the finding that the predictive ratios of the TPIPDCG model approximated unity better than those of the demographic model in all subgroups indicates that the capitation payment as predicted by the TPIPDCG model for each subgroup would better correlate to the actual spending. CONCLUSION: Taiwan's risk-adjusted capitation model based on principal inpatient diagnoses has higher predictability on individual's future expenditure than its counterpart in the USA. This finding provides insight into not only the development of Taiwan's diagnosis-based risk adjustment models but also the necessity of modification when applying foreign-developed risk adjustment models to the NHI.

Vitamin/calcium supplement use in Taiwan: findings from the 1994 National Health Interview Survey.

This study aimed to provide the prevalence of vitamin/calcium supplement use and, to explore the gender differences in and the correlates of supplement use. Data came from the 1994 National Health Interview Survey of 3,814 households; and 7,019 respondents (3,561 females and 3,458 males) aged 25 years old and older were included in the analysis. Supplement users were defined as individuals who reported taking any supplements at least once a week. Associations between supplement use and its correlates were examined by using chi-square analysis and logistic regression. The results indicated that 22.2% of females and 12.7% of males used vitamin supplement, and 10.2% of females and 3.7% of males took calcium supplement. The adjusted sex odds ratio was 2.8 (95% CI = 2.4-3.2) for vitamin supplement use and 3.8 (95% CI = 3.0-4.7) for calcium supplement use when sociodemographic and health variables were controlled. Increased likelihood on the use of vitamin/calcium supplement was associated with sociodemographic characteristics (females, over 45 years old, more educated) and health behaviors (more regular exercise and check on blood pressure). Additionally, females who received regular Pap smear or with no chronic disease tended to take more vitamin supplement and females who perceived themselves with a poor health condition were more likely to use calcium supplement than others.

Healthcare utilization patterns and risk adjustment under Taiwan's National Health Insurance system.

BACKGROUND AND PURPOSE: Some recent proposals for reform of Taiwan's National Health Insurance (NHI) system include risk adjustment mechanisms. However, there is a paucity of research on risk adjustment and its utilization in health insurance systems in Taiwan. The purposes of this study were to determine the healthcare utilization pattern and to develop a risk assessment model for capitation payments under NHI. METHODS: The individual enrollment and medical expenditure data for 1996 and 1997 were obtained from the Bureau of NHI. A random sample of 360,037 beneficiaries was divided into two sub-samples: one for model building and one for validation. Linear regression was employed to estimate the relationship between each individual's 1997 total expenditure and risk adjusters, i.e., age, gender, prior years' medical spending, and catastrophic status. RESULTS: The 10- to 14-years age group had the lowest total expenditure of $NT 3,055 ($US 1 = $NT 27.5 in 1996) in 1996, while the 65 years and over age group had the highest at almost 10 times more than the lowest. The distributions of total expenditure for both genders followed the familiar J-shaped curve. The average of the total expenditure of individuals with a catastrophic diagnosis was more than 17 times that of individuals without. Age and gender resulted in a predictive R2 of only 3.8% in the risk assessment model. By including prior total expenditure, the predictive R2 increased to 24.2%. Further addition of catastrophic status increased the predictability slightly to 25%. Prior outpatient expenditure predicted 72% of subsequent outpatient expenditure, but prior inpatient expenditure predicted only 3% of subsequent inpatient expenditure. CONCLUSIONS: As in other countries, age and gender provided only limited predictability in risk assessment. On the other hand, prior outpatient expenditure in this study provided relatively superior predictability in risk assessment. Prudence is required when including prior utilization as a part of the risk assessment model in calculating capitation payments, as this may indirectly encourage unnecessary use of healthcare services.