Not too shy to point! Exploring the relationship between shyness and pointing in the second year.

Infants' use of pointing gestures to direct and share attention develops during the first 2 years of life. Shyness, defined as an approach-avoidance motivational conflict during social interactions, may influence infants' use of pointing. Recent research distinguished between positive (gaze and/or head aversions while smiling) and non-positive (gaze and/or head aversions without smiling) shyness, which are related to different social and cognitive skills. We investigated whether positive and non-positive shyness in 12-month-old (n = 38; 15 girls) and 15-month-old (n = 45; 15 girls) infants were associated with their production of pointing gestures. Infants' expressions of shyness were observed during a social-exposure task in which the infant entered the laboratory room in their parent's arms and was welcomed by an unfamiliar person who provided attention and compliments. Infants' pointing was measured with a pointing task involving three stimuli: pleasant, unpleasant, and neutral. Positive shyness was positively associated with overall pointing at 15 months, especially in combination with high levels of non-positive shyness. In addition, infants who displayed more non-positive shyness pointed more frequently to direct the attention of the social partner to an unpleasant (vs. neutral) stimulus at both ages. Results indicate that shyness influences the early use of pointing to emotionally charged stimuli.

Predicting pointing from early socioemotional communication with mothers, fathers, and strangers through the lens of temperamental reactivity.

Socioemotional and referential communication are primary expressions of interpersonal engagement in infancy and beyond. Early socioemotional communication in dyadic interactions may form a foundation for triadic referential communication and gesture production, yet the role of temperament in moderating their association has not been examined. We investigated whether early socioemotional communication behaviors, and infant temperamental reactivity, were associated with later pointing production. Participants were 51 infants (45% girls) and both their parents (86.5% Dutch). Early infant socioemotional communication (production of smile, vocalizations, and gaze) was observed during separate home-based face-to-face interactions with mothers, fathers, and strangers at 4 and 8 months. At both ages, mothers and fathers reported on infant temperamental surgency and negative affectivity, and overall means were calculated. Referential communication (declarative pointing) was measured during structured lab-based observations at 12 and 15 months. Socioemotional and referential communication behaviors were microanalytically coded second by second. Poisson multilevel regression analyses indicated interaction effects between temperament and smile, vocalizations, and gazes to the adult's face with each partner in predicting pointing. High levels of infant temperamental surgency tended to enhance positive associations between early socioemotional communication behaviors with mothers and fathers and pointing. By contrast, high levels of negative affectivity tended to dampen associations between early communication behaviors with strangers and pointing. Results highlight the importance of infant socioemotional communication with diverse partners and the moderating role of temperamental reactivity in predicting referential communication. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Implications of the syntheses on definition, theory, and methods conducted by the Response Shift - in Sync Working Group.

PURPOSE: Our aim is to advance response shift research by explicating the implications of published syntheses by the Response Shift - in Sync Working Group in an integrative way and suggesting ways for improving the quality of future response shift studies. METHODS: Members of the Working Group further discussed the syntheses of the literature on definitions, theoretical underpinnings, operationalizations, and response shift methods. They outlined areas in need of further explication and refinement, and delineated additional implications for future research. RESULTS: First, the proposed response shift definition was further specified and its implications for the interpretation of results explicated in relation to former, published definitions. Second, the proposed theoretical model was further explained in relation to previous theoretical models and its implications for formulating research objectives highlighted. Third, ways to explore alternative explanations per response shift method and their implications for response shift detection and explanation were delineated. The implications of the diversity of the response shift methods for response shift research were presented. Fourth, the implications of the need to enhance the quality and reporting of the response shift studies for future research were sketched. CONCLUSION: With our work, we intend to contribute to a common language regarding response shift definitions, theory, and methods. By elucidating some of the major implications of earlier work, we hope to advance response shift research.

Response Shift After Cognitive Behavioral Therapy Targeting Severe Fatigue: Explorative Analysis of Three Randomized Controlled Trials.

BACKGROUND: Cognitive behavioral therapy (CBT) is an evidence-based intervention for severe fatigue. Changes in patients' fatigue scores following CBT might reflect not only the intended relief in fatigue but also response shift, a change in the meaning of patients' self-evaluation. Objectives were to (1) identify the occurrence of response shift in patients undergoing CBT, (2) determine the impact of response shift on the intervention effect, and (3) investigate whether changes in fatigue-related cognitions and perceptions, targeted during CBT, are associated with response shift. METHODS: Data of three randomized controlled trials testing the efficacy of CBT in individuals with chronic fatigue syndrome (CFS, n = 222), cancer (n = 123), and diabetes (n = 107) were re-analyzed. Fatigue severity was measured with 8 items from the Checklist Individual Strength, a valid and widely used self-report questionnaire. Structural equation modelling was applied to assess lack of longitudinal measurement invariance, as indication of response shift. RESULTS: As expected, in all three trials, response shift was indicated in the CBT groups, not the control groups. Response shift through reprioritization was indicated for the items "Physically, I feel exhausted" (CFS) and "I tire easily" (cancer, diabetes), which became less vs. more important to the measurement of fatigue, respectively. However, this did not affect the intervention effects. Some changes in cognitions and perceptions were associated with the response shifts. CONCLUSIONS: CBT seems to induce response shift through reprioritization across patient groups, but its occurrence does not affect the intervention effect. Future research should corroborate these findings and investigate whether patients indeed change their understanding of fatigue.

Beyond the familial: The development of emotional communication with mothers, fathers, and strangers.

Interaction with unfamiliar partners is a component of social life from infancy onward. Yet little is known about preverbal communication with strangers. This study compared the development of infant communication with strangers to communication with mothers and fathers and examined the contribution of temperament to partner-specific communication patterns. A sample of 58 infants was observed at four and eight months during separate home-based face-to-face interactions with three partners (mother, father, and stranger). Infant visual, facial, and vocal communication behaviors were coded microanalytically. Each parent reported on infant temperament at both ages. Multilevel regression analyses indicated that infants gazed longer at strangers than at fathers, exhibited less smiling to strangers than to mothers, and produced fewer vocalizations with strangers than with either parent. Both age and temperament moderated these differences. Vocal communication with fathers became more frequent at eight months; smiling to mothers was accentuated among infants with higher levels of temperamental surgency. Importantly, levels of communication behaviors with strangers were concurrently and longitudinally associated with those with mothers and fathers. Overall, findings suggest that infant emotional communication patterns are modulated by individual temperamental differences and are reproduced in and over time, though at different levels, when interacting with novel partners.

Response shift after coronary revascularization.

PURPOSE: The aims of this study were to investigate (1) the extent to which response shift occurs among patients with coronary artery disease (CAD) after coronary revascularization, (2) whether the assessment of changes in health-related quality of life (HRQoL), controlled for response shift, yield more valid estimates of changes in HRQoL, as indicated by stronger associations with criterion measures of change, than without controlling for response shift, and (3) if occurrences of response shift are related to patient characteristics. METHODS: Patients with CAD completed the SF-36 and the Seattle Angina Questionnaire (SAQ7) at baseline and 3 months after coronary revascularization. Sociodemographic, clinical and psychosocial variables were measured with the patient version of the New York Heart Association-class, Subjective Significance Questionnaire, Reconstruction of Life Events Questionnaire (RE-LIFE), and HEXACO personality inventory. Oort's Structural Equation Modeling (SEM) approach was used to investigate response shift. RESULTS: 191 patient completed questionnaires at baseline and at 3 months after treatment. The SF-36 showed recalibration and reprioritization response shift and the SAQ7 reconceptualization response shift. Controlling for these response shift effects did not result in more valid estimates of change. One significant association was found between reprioritization response shift and complete integration of having CAD into their life story, as indicated by the RE-LIFE. CONCLUSION: Results indicate response shift in HRQoL following coronary revascularization. While we did not find an impact of response shift on the estimates of change, the SEM approach provides a more comprehensive insight into the different types of change in HRQoL following coronary revascularization.

Response shift in patient-reported outcomes: definition, theory, and a revised model.

PURPOSE: The extant response shift definitions and theoretical response shift models, while helpful, also introduce predicaments and theoretical debates continue. To address these predicaments and stimulate empirical research, we propose a more specific formal definition of response shift and a revised theoretical model. METHODS: This work is an international collaborative effort and involved a critical assessment of the literature. RESULTS: Three main predicaments were identified. First, the formal definitions of response shift need further specification and clarification. Second, previous models were focused on explaining change in the construct intended to be measured rather than explaining the construct at multiple time points and neglected the importance of using at least two time points to investigate response shift. Third, extant models do not explicitly distinguish the measure from the construct. Here we define response shift as an effect occurring whenever observed change (e.g., change in patient-reported outcome measures (PROM) scores) is not fully explained by target change (i.e., change in the construct intended to be measured). The revised model distinguishes the measure (e.g., PROM) from the underlying target construct (e.g., quality of life) at two time points. The major plausible paths are delineated, and the underlying assumptions of this model are explicated. CONCLUSION: It is our hope that this refined definition and model are useful in the further development of response shift theory. The model with its explicit list of assumptions and hypothesized relationships lends itself for critical, empirical examination. Future studies are needed to empirically test the assumptions and hypothesized relationships.

Infant Emotional Mimicry of Strangers: Associations with Parent Emotional Mimicry, Parent-Infant Mutual Attention, and Parent Dispositional Affective Empathy.

Emotional mimicry, the tendency to automatically and spontaneously reproduce others' facial expressions, characterizes human social interactions from infancy onwards. Yet, little is known about the factors modulating its development in the first year of life. This study investigated infant emotional mimicry and its association with parent emotional mimicry, parent-infant mutual attention, and parent dispositional affective empathy. One hundred and seventeen parent-infant dyads (51 six-month-olds, 66 twelve-month-olds) were observed during video presentation of strangers' happy, sad, angry, and fearful faces. Infant and parent emotional mimicry (i.e., facial expressions valence-congruent to the video) and their mutual attention (i.e., simultaneous gaze at one another) were systematically coded second-by-second. Parent empathy was assessed via self-report. Path models indicated that infant mimicry of happy stimuli was positively and independently associated with parent mimicry and affective empathy, while infant mimicry of sad stimuli was related to longer parent-infant mutual attention. Findings provide new insights into infants' and parents' coordination of mimicry and attention during triadic contexts of interactions, endorsing the social-affiliative function of mimicry already present in infancy: emotional mimicry occurs as an automatic parent-infant shared behavior and early manifestation of empathy only when strangers' emotional displays are positive, and thus perceived as affiliative.

Response shift in results of patient-reported outcome measures: a commentary to The Response Shift-in Sync Working Group initiative.

PURPOSE: The Working Group undertook a critical, comprehensive synthesis of the response shift work to date. We aimed to (1) describe the rationale for this initiative; (2) outline how the Working Group operated; (3) summarize the papers that comprise this initiative; and (4) discuss the way forward. METHODS: Four interdisciplinary teams, consisting of response shift experts, external experts, and new investigators, prepared papers on (1) definitions and theoretical underpinnings, (2) operationalizations and response shift methods, (3) implications for healthcare decision-making, and (4) on the published magnitudes of response shift effects. Draft documents were discussed during a two-day meeting. Papers were reviewed by all members. RESULTS: Vanier and colleagues revised the formal definition and theory of response shift, and applied these in an amended, explanatory model of response shift. Sébille and colleagues conducted a critical examination of eleven response shift methods and concluded that for each method extra steps are required to make the response shift interpretation plausible. Sawatzky and colleagues created a framework for considering the impact of response shift on healthcare decision-making at the level of the individual patient (micro), the organization (meso), and policy (macro). Sajobi and colleagues are conducting a meta-analysis of published response shift effects. Preliminary findings indicate that the mean effect sizes are often small and variable across studies that measure different outcomes and use different methods. CONCLUSION: Future response shift research will benefit from collaboration among diverse people, formulating alternative hypotheses of response shift, and conducting the most conclusive studies aimed at testing these (falsification).

Analytical power calculations for structural equation modeling: A tutorial and Shiny app.

Conducting a power analysis can be challenging for researchers who plan to analyze their data using structural equation models (SEMs), particularly when Monte Carlo methods are used to obtain power. In this tutorial, we explain how power calculations without Monte Carlo methods for the χ2 test and the RMSEA tests of (not-)close fit can be conducted using the Shiny app "power4SEM". power4SEM facilitates power calculations for SEM using two methods that are not computationally intensive and that focus on model fit instead of the statistical significance of (functions of) parameters. These are the method proposed by Satorra and Saris (Psychometrika 50(1), 83-90, 1985) for power calculations of the likelihood ratio test, and that described by MacCallum, Browne, and Sugawara (Psychol Methods 1(2) 130-149, 1996) for RMSEA-based power calculations. We illustrate the use of power4SEM with examples of power analyses for path models, factor models, and a latent growth model.

Well-being of mothers with epilepsy with school-aged children.

PURPOSE: The purpose of the study was to examine different aspects of well-being in mothers with epilepsy with school-aged children. METHODS: In an observational study, mothers, identified from the European Registry of Antiepileptic Drugs and Pregnancy database in the Netherlands, completed questions on epilepsy, the impact of epilepsy on daily functioning, quality of life, behavioral problems, and parenting stress. Descriptive analyses were performed to examine the prevalence of behavioral problems and the impact of epilepsy on different aspects of the mother's daily functioning and family life. We subsequently investigated which factors contributed most to the impact of maternal epilepsy using regression analyses. RESULTS: One hundred fifty-six (46%) of the 342 invited mothers with epilepsy participated. The majority (89%) had low epilepsy severity, with well-controlled seizures. Internalizing problems within the borderline or clinical range were reported by 23% of the mothers. Behavioral problems were significantly correlated with epilepsy severity (r = 0.26, p = .002), impact of epilepsy on daily functioning (r = 0.32, p < .001), and quality of life (r = -0.52, p < 01). Quality of life was in general good (mean = 8, standard deviation [SD] = 1), with low impact of epilepsy. Epilepsy affected mostly maternal self-confidence, work, and general health. Mothers indicated to experience no to little impact of epilepsy on the relationship with their children, partner, or family. Regression analyses showed that epilepsy severity (1.0, 95% confidence interval [CI]: 0.4 to 1.6; p = .002) and quality of life (-1.3, CI: -2.3 to -0.4; p = .007) were significant contributors to the impact of epilepsy on daily functioning, while other factors (maternal education, family type, behavioral problems, and parenting stress) were nonsignificant. DISCUSSION: The current study shows that mothers with epilepsy generally fared well. Epilepsy negatively impacted the lives of some mothers, though. As maternal well-being is of importance for mother-child interaction and child development, clinicians should be aware of the impact of epilepsy on maternal psychosocial outcomes and family life of women with epilepsy.

Neurocognition after prenatal levetiracetam, lamotrigine, carbamazepine or valproate exposure.

OBJECTIVE: To examine neurocognitive functioning of children exposed prenatally to carbamazepine, lamotrigine, levetiracetam or valproate monotherapy. METHODS: In a prospective observational study, children aged 6 or 7 years, identified from the European Registry of Antiepileptic Drugs and Pregnancy database in The Netherlands, were assessed using the Wechsler Intelligence Scale for Children and the developmental neuropsychological assessment. Maternal IQ was measured using Wechsler Adult Intelligence Scale. Assessors were blinded to drug exposures. RESULTS: One hundred and sixty-one children (one set of twins and 21 sibling pairs) of 139 mothers were included. As a group, children achieved average scores on neurocognitive outcomes. Children exposed to valproate (n = 22) performed lower on all six neurocognitive domains, especially language, than those exposed to carbamazepine (n = 32), lamotrigine (n = 82) or levetiracetam (n = 25). After controlling for maternal IQ and drug dose, the verbal IQ of valproate-exposed children was on average 9.1 points lower than those exposed to carbamazepine (95% confidence interval [CI] 1.3-17.0; p = 0.023), 10.3 lower than lamotrigine-exposed children (CI 3.4-17.3; p = 0.004) and 13.4 lower than levetiracetam-exposed children (CI 5.2-21.6; p = 0.002). No significant dose-effect was found. Virtually no significant differences were found between lamotrigine and levetiracetam or lamotrigine and carbamazepine exposed children. CONCLUSIONS: Consistent with previous research, valproate-exposed children experienced more problems compared to three other common antiepileptic drugs, while children exposed to lamotrigine, carbamazepine or levetiracetam revealed little to no problems. This illustrates the need for systematic follow-up of prenatally exposed children, to support pre-pregnancy counseling and treatment decisions in women of reproductive age.

Behavioral problems in children of mothers with epilepsy prenatally exposed to valproate, carbamazepine, lamotrigine, or levetiracetam monotherapy.

OBJECTIVE: To examine the behavioral functioning of children prenatally exposed to carbamazepine (CBZ), lamotrigine (LTG), levetiracetam (LEV), or valproate (VPA) monotherapy. METHODS: In collaboration with the European Registry of Antiepileptic Drugs and Pregnancy (EURAP), the Dutch EURAP & Development study was designed, a prospective observational study. Between January 2015 and March 2018, the Child Behavior Checklist and the Social Emotional Questionnaire were used to examine the nature and severity of behavioral problems. VPA-exposed children were compared to children exposed to CBZ, LTG, or LEV, taking potential confounders into account. A direct comparison was also made between LTG and LEV, as these are first-choice treatments for many women with epilepsy of childbearing potential. RESULTS: Of the 405 invited, 181 children were included; 26 were exposed to VPA, 37 to CBZ, 88 to LTG, and 30 to LEV. For most children, both parents completed the behavioral questionnaires. Across all four antiepileptic drug (AED) exposure groups, high percentages of children with clinically relevant behavior problems were found, with behavioral problems occurring in 32% of VPA-exposed children, 14% of CBZ, 16% of LTG, and 14% of LEV. After controlling for potential confounders, VPA-exposed children had significantly more social problems than those exposed to LTG (-2.8, 95% confidence interval [CI] = -5.2 to -0.4; P = 0.022) or LEV (-3.2, CI: -6.1 to -0.3; P = 0.028), and significantly more attention problems than LEV-exposed children (-3.7, CI: -6.7 to -0.8; P = 0.013). LTG-exposed children had significantly more attention deficit (-9.2, CI: -17.3 to 1.1; P = 0.026), but significantly less anxious behavior when compared to LEV-exposed children (9.0, CI: 0.3-17.6; P = 0.042). SIGNIFICANCE: Compared to population norms, a high proportion of children of mothers with epilepsy exposed prenatally to monotherapy with four common AEDs had clinical behavioral problems reported by parents. Different patterns were seen, with some but not all subscales raised for all AED exposure groups. It is important that prenatally AED-exposed children are regularly screened for behavioral problems so that appropriate help can be provided.

Maternal epilepsy and behavioral development of the child: Family factors do matter.

PURPOSE: The purpose of the study was to examine whether mothers with epilepsy experience family problems and to investigate the possible mediating role of distinct family factors in the relationship between maternal epilepsy and child behavioral problems, in which it is also investigated whether more proximal family factors mediate the more distal family factors. METHODS: In an observational study, with children identified from the European Registry of Antiepileptic Drugs and Pregnancy database in the Netherlands (EURAP-NL), parents completed questionnaires on maternal epilepsy, family factors (proximal, distal, contextual, global), and child behavior. Hierarchical multilevel regression analyses were performed to examine the relative contribution of epilepsy-related and family factors on child internalizing and externalizing problems. RESULTS: Between January 2015 and March 2018, the questionnaires were completed for 175 children. Mothers with epilepsy showed significantly more parenting stress and problems with parenting than mothers from the general population. Family factors were significantly associated with child behavioral problems. For internalizing problems, maternal epilepsy, global, contextual, and distal family factors were each found to have significant added value. Distal family factors contributed most to internalizing problems and showed a mediating role for epilepsy-related factors and previous added family factors in the model. Global, contextual, distal, and proximal factors were all found to be significant contributors to externalizing problems, with the factor most proximal to the child (quality of parent-child interaction) showing the largest effect. DISCUSSION: Including family factors in research regarding children of mothers with epilepsy is important as they can have a contribution additional to the teratogenic risks of prenatal exposure to antiepileptic drugs (AEDs). Family factors, in particular distal and proximal family factors, can weaken or strengthen child development and may provide starting points for interventions.

Risk factors for child sexual abuse victimization: A meta-analytic review.

Experiencing child sexual abuse (CSA) is a major public health problem with serious consequences for CSA victims. For effective assessment and (preventive) intervention, knowledge on risk factors and their effects is crucial. Here, the aim was to synthesize research on associations between (putative) risk factors and CSA victimization. In total, 765 (putative) risk factors were extracted from 72 studies, which were classified into 35 risk domains. A series of three-level meta-analyses produced a significant mean effect for 23 of the 35 risk domains ranging from r = .101 to r = .360. The strongest effects were found for prior victimization of the child and/or its family members, such as prior CSA victimization of the child and/or siblings (r = .360), prior victimization of the child other than child abuse (r = .340), prior or concurrent forms of child abuse in the child's home environment (r = .267), and a parental history of child abuse victimization (r = .265). Other identified risks were related to parental problems (e.g., intimate partner violence, r = .188), parenting problems (e.g., low quality of parent-child relation, r = .292), a non-nuclear family structure (e.g., having a stepfather, r = .118), family problems (e.g., social isolation, r = .191), child problems (e.g., having a mental/physical chronic condition, r = .193), and other child characteristics (e.g., being female, r = .290). Moderator analyses suggested that contact CSA victimization may be better predicted than noncontact CSA victimization. It was concluded that an ecological perspective on preventing CSA victimization is necessary. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Parental negative emotions are related to behavioral and pupillary correlates of infants' attention to facial expressions of emotion.

Previous evidence revealed links between maternal negative emotions and infants' attention to facial expressions of emotion in clinical and community samples. This study investigated the associations between infants' attention to emotional faces and infants' and parents' negative emotions in a community sample. Infants' (N = 57, Mage = 14.26 months) fixations and pupil responses to fearful, sad, angry versus happy and neutral faces were measured with an eye-tracker. Mothers' and fathers' negative emotions (negative affect, depression, and anxiety), and infants' negative temperament were measured with questionnaires. Infants looked longer at fearful than happy or neutral faces, while they showed less pupil dilation to fearful than to happy or neutral faces. Higher levels of maternal negative emotions were related to less pupillary arousal to emotional facial expressions in infants, while paternal negative emotions did not predict infants' pupil responses. Exploratory analyses suggested a significant link between paternal but not maternal negative emotions and infants' fixations that was moderated by infant negative temperament: Higher levels of negative emotions in fathers were related to longer fixations in children with high levels of negative temperament, while it was related to shorter fixations in infants with low levels of negative temperament. The findings provide support for the idea that exposure to mothers' and fathers' negative emotions play a role on the development of infants' attention to facial expressions in typical development.

Exposure to antiepileptic drugs in pregnancy: The need for a family factor framework.

PURPOSE: Children exposed to antiepileptic drugs (AEDs) in utero are at risk for developmental problems. Maternal epilepsy, its impact on the family system, and other family factors may also contribute. We reviewed the possible associations between family factors and developmental outcome in children who had been exposed to AED during pregnancy. METHODS: We conducted a narrative review and searched MEDLINE, Embase, Google Scholar, and PsycINFO on the following terms: in utero exposure, pregnancy outcome, and AEDs. A family factor framework (the ABCX model) served as the basis to review distinct family factors in children who were exposed to AEDs in pregnancy. RESULTS: Few studies have investigated these factors. Mothers with epilepsy have problems caring for themselves and for the child and experience more parenting stress. There is a paucity of studies of the possible impact of family factors on the neurocognitive and behavioral development of children of mothers with epilepsy. DISCUSSION: Further work is required to ascertain which family factors are associated with child development in addition to the effects of AED exposure and their potential interaction. As epilepsy may have considerable impact on intrafamily factors and as children are especially vulnerable to such effects, study designs incorporating family factors should be encouraged.

Chronic sleep reduction in adolescents-clinical cut-off scores for the Chronic Sleep Reduction Questionnaire (CSRQ).

The Chronic Sleep Reduction Questionnaire is a validated questionnaire that measures symptoms of prolonged insufficient and/or poor sleep and therefore accounts for individuals' sleep need and sleep debt. This study extends its psychometric properties by providing cut-off scores, using a matched sample of 298 healthy adolescents (15.38 ± 1.63 years, 37.9% male, mean Chronic Sleep Reduction Questionnaire score: 32.98 ± 6.51) and 298 adolescents with insomnia/delayed sleep-wake phase disorder (15.48 ± 1.62 years; 37.9% male, mean Chronic Sleep Reduction Questionnaire score: 42.59 ± 7.06). We found an area under the curve of 0.84 (95% confidence interval: 0.81-0.87). Cut-off scores for optimal sensitivity, optimal specificity and based on Youden's criterion are provided. These cut-off scores are highly relevant for use of the Chronic Sleep Reduction Questionnaire in future studies and clinical practice.