Development and validation of a patient-assessed gastroparesis symptom severity measure: the Gastroparesis Cardinal Symptom Index

BACKGROUND: Patient-based symptom assessments are necessary to evaluate the effectiveness of medical treatments for gastroparesis. AIM: To summarize the development and measurement qualities of the Gastroparesis Cardinal Symptom Index (GCSI), a new measure of gastroparesis-related symptoms. METHODS: The GCSI was based on reviews of the medical literature, clinician interviews and patient focus groups. The measurement qualities (i.e. reliability, validity) of the GCSI were examined in 169 gastroparesis patients. Patients were recruited from seven clinical centres in the USA to participate in this observational study. Patients completed the GCSI, SF-36 Health Survey and disability day questions at a baseline visit and again after 8 weeks. Clinicians independently rated the severity of the patients' symptoms, and both clinicians and patients rated the change in gastroparesis-related symptoms over the 8-week study. RESULTS: The GCSI consists of three sub-scales: post-prandial fullness/early satiety, nausea/vomiting and bloating. The internal consistency reliability was 0.84 and the test-re-test reliability was 0.76 for the GCSI total score. Significant relationships were observed between the clinician-assessed symptom severity and the GCSI total score, and significant associations were found between the GCSI scores and SF-36 physical and mental component summary scores and restricted activity and bed disability days. Patients with greater symptom severity, as rated by clinicians, reported greater symptom severity on the GCSI. The GCSI total scores were responsive to changes in overall gastroparesis symptoms as assessed by clinicians (P = 0.0002) and patients (P = 0.002). CONCLUSION: The findings of this study indicate that the GCSI is a reliable and valid instrument for measuring the symptom severity in patients with gastroparesis.     

Validation of a symptom diary for patients with gastro-oesophageal reflux disease

BACKGROUND: Symptom diaries are potentially attractive but, because of concerns about patient compliance, they have had limited use in clinical trials. We assessed the validity and responsiveness of a symptom diary for patients with gastro-oesophageal reflux disease. METHODS: We included 215 patients with gastro-oesophageal reflux disease after starting treatment for 4 weeks with 40 mg esomeprazole once daily. Patients recorded whether they experienced night-time heartburn (yes/no), the severity of daytime heartburn on a scale from 1 (no heartburn) to 4 (severe heartburn) and their antacid use. Patients also completed a number of disease-specific and preference-based Health-related Quality of Life questionnaires at baseline and follow-up. RESULTS: Consistent with a priori predictions, daytime heartburn showed moderate to strong correlations with the Quality of Life in Reflux and Dyspepsia questionnaire (0.36-0.67) and four scales of symptom severity (0.36-0.70) for baseline, follow-up and change scores, but low correlations with the Standard Gamble. Responsiveness of the daytime heartburn item was excellent with a mean change from baseline to follow-up of -1.3 (95% CI -1.4 to -1.1) and a standardized response mean of 1.33 while responsiveness of the daily antacid use item was moderate (mean change scores -1.8 tablets taken, 95% CI -2.3 to -1.3 and standardized response mean of 0.64). CONCLUSIONS: The excellent psychometric properties of this simple gastro-oesophageal reflux disease diary make it an attractive measure for future trials.     

Withdrawal symptom after discontinuation of transdermal fentanyl at a daily dose of 0.6 mg

Neurophysiologic disorders developed in three patients after discontinuation of transdermal fentanyl (TDF) at a daily dose of 0.6mg (2.5mg per a patch), although direct removal of a 2.5mg patch is permitted by the manufacturer as the formulation has the lowest fentanyl content among all the commercially available patch formulations. These observations indicate that the discontinuation of TDF carries a risk for developing withdrawal symptoms even when using a 2.5mg patch. To avoid such adverse events, we considered the necessity of gradual reduction in the daily fentanyl requirements. For this purpose, we covered part of the application surface of the patch with an insulating tape, and then increased the covered area in a stepwise manner. There were no apparent withdrawal signs during the procedure described above.     

Reliability and validity of the addiction severity index with a homeless sample

The Addiction Severity Index (ASI) is an instrument widely used to assess the treatment problems of substance users. Its psychometric properties have been tested and found satisfactory for many types of substance abusers entering treatment. However, there are many other subgroups of substance users not in formal treatment, such as homeless substance users. While the ASI has been used with this subgroup, its psychometric properties remain questionable. This study examined the reliability and validity of the ASI in a sample of 98 homeless substance users awaiting temporary housing placement. Test-retest reliability found the ASI to have moderate to high reliability coefficients in each of the seven domains assessed. Both composite score and severity rating measures were found to be quite independent with low intercorrelations. Three of the seven ASI composite scores were tested for and found to have moderate concurrent validity: alcohol (r = .31 to .36), drug (r = .46), and psychiatric (r = .53 to .66). Composite score interitem correlations were .70 or greater in each of the domains except for employment (.50) and family (.52). These data suggest that, although there are some limitations in using the ASI with homeless substance users, it demonstrated acceptable reliability and validity.     

Adolescent nicotine dependence symptom profiles and risk for future daily smoking

Recent research on adolescent smokers suggests that there are important differences in the types of nicotine dependence (ND) symptoms that emerge and different patterns of ND symptoms. The purpose of this study was to use data from the longitudinal Social and Emotional Contexts of Adolescent Smoking Patterns Study to identify latent subgroups of adolescent experimental and nondaily smokers varying in number and types of endorsed ND symptoms. Profiles were identified using baseline level of smoking, individual patterns of ND symptoms and other ND risk factors. Discrete time survival analysis was used to examine profile differences in probability of becoming daily smokers 48 months later. Four distinct subgroups of smokers with different patterns of smoking behavior, ND symptoms, and alcohol and other substance use emerged. Heavier smoking adolescents with high symptom endorsement, particularly the need to smoke in the morning, were most likely to become daily smokers 48 months later. A subgroup of social smokers had high smoking exposure and symptom endorsement (except need to smoke in the morning), and high levels of other substance use. Despite lower rates of smoking frequency and quantity compared to the heavier smoking class, 36% of these adolescents smoked daily by 48 months, with a steeper decline in survival rates compared to other lighter smoking classes. Morning smoking symptoms and symptoms prioritizing smoking (i.e., choosing to spend money on cigarettes instead of lunch or smoking when ill or where smoking is forbidden) might quickly identify adolescent non-daily smokers with more severe dependence and higher risk for daily smoking. A focus on skills for avoiding social situations involving use of alcohol and other drugs and reducing peer smoking influences may be an important focus for reducing smoking and other substance use among social smokers.     

Evaluation of methods used for estimating content validity

The assessment of content validity is a critical and complex step in the development process of instruments which are frequently used to measure complex constructs in social and administrative pharmacy research. The aims of this study were to investigate the elements of content validity; to describe a practical approach for assessing content validity; and to discuss existing content validity indices. This is a narrative review of the assessment and quantification of content validity. It describes the key stages of conducting the content validation study and discusses the quantification and evaluation of the content validity estimates. Content validity provides evidence about the degree to which elements of an assessment instrument are relevant to and representative of the targeted construct for a particular assessment purpose. The assessment of content validity relies on using a panel of experts to evaluate instrument elements and rate them based on their relevance and representativeness to the content domain. It is a three-stage process that includes; the development stage, judgment and quantifying stage, and revising and reconstruction stage. To quantify the expert judgments, several indices have been discussed in this paper such as the content validity ratio (CVR), content validity index (CVI), modified–Kappa, and some agreement indices. A practical guide describes the process of content validity evaluation is provided. In summary, content validation processes and content validity indices are essential factors in the instrument development process, should be treated and reported as important as other types of construct validation. Determining item CVI and reporting an overall CVI are important components necessary to instruments especially when the instrument is used to measure health outcomes or to guide a clinical decision making. Content validity deserves a rigorous assessment process as the obtained information from this process are invaluable for the quality of the newly developed instrument.     

Investigating the criterion validity of psychiatric symptom scales using surrogate marker validation methodology

This work investigates whether techniques that are generally used for the validation of surrogate markers in clinical trials can be applied in the validation of psychiatric health measurements (often scales) and more generally to investigate relationships between treatment effects on different measurements. However, the categorical nature of some scales makes these techniques inapplicable in the way they were originally defined. In this work, we show a possible extension of this methodology to the setting in which one of the scales is an ordinal categorical variable. When psychiatric health measurements are either developed or used in a new population, reliability and validity must be investigated. Reliability, more specifically internal consistency, test-retest reliability, and inter-rater reliability, is focused on the reproducibility of the measurement. Validity is defined as the degree to which the scale measures what it purports to measure. This can be performed through the analysis of content, construct, and criterion validity. We argue that recent methodology, in particular developed to study surrogate endpoints, can be used to examine criterion validity, concurrent validity, and predictive validity. In concurrent validity, we correlate the measurement with a criterion measure, both of which are given at the same time. In predictive validity, the criterion will not be available to some point in time in the future. The surrogate methods were applied on pooled data from five trials in schizophrenia.     

Variations in parthenolide content and daily dose of feverfew products.

Variations in the parthenolide content of feverfew products available to consumers were studied. Feverfew products were analyzed for the content of parthenolide, the purported active component. The actual weight of feverfew was determined only in those products containing dried feverfew leaf. The total daily doses of feverfew leaf and parthenolide were calculated by using the instructions on each product label. Parthenolide content was determined by high-performance liquid chromatography. The quantity of feverfew leaf in each capsule was similar to that stated on the label and ranged from 25 to 500 mg. Parthenolide content per dosage form varied 150-fold (from 0.02 to 3.0 mg), while percent parthenolide varied 5.3-fold (from 0.14% to 0.74%). If a person consumed the daily dose recommended on the label, intake of dried feverfew leaf would range from 225 to 2246 mg/day, a 10-fold variation, while intake of parthenolide would range from 0.06 to 9.7 mg/day, a 160-fold variation. Large variations were observed in the parthenolide contents and daily intake as recommended by the labeling in commercial feverfew products.     

Magnesium content in daily food portions and the influence of supplementation

Magnesium is one of the most important cations for an organism. The aim of our study is to evaluate whether the use of a magnesium formulation as a diet supplement or medical treatment is necessary. The 24-hour recall method was used to obtain information regarding the daily magnesium consumption of 949 people. The results were compared with the Estimated Average Requirement (EAR) and Recommended Daily Allowance (RDA) values. The average daily requirement for magnesium was exceeded by 292 (183 women and 109 men) of the 949 respondents. This research confirmed excessive magnesium intake by both men and women that exceeded both the EAR and the RDA. Uncontrolled, excessive dietary supplementation or medical treatment with magnesium by this group may constitute a health threat.     

医院感染绩效考核指标量表的信效度研究

目的检验自制的医院感染绩效考核指标量表的信度和效度。方法利用指标量表对莆田地区3所三级甲等医院120名医务人员进行测试,2周后进行复测,对该量表内容效度和结构效度,以及内部一致性信度、重测信度进行验证。结果量表的重测信度为0.937,Cronbachsα系数为0.914,信度较高。量表内容效度较好,相关性分析和因子分析表明此量表有较好的结构效度。结论医院感染绩效考核指标量表具有较好的信度和效度,在医院感染绩效管理中能够对医务人员进行较为公正、客观的评价。     

Coping via substance use,internal attribution bias,and their depressive interplay: Findings from a three-week daily diary study using a clinical sample

BackgroundThe relationship between depression and coping-oriented substance use is extensively documented; however, the cognitive processes moderating this bidirectional relationship are not well-understood. The present study investigated whether internal attribution bias coupled with a tendency to use drugs and/or alcohol to cope predicts increases in depression and daily-levels of general negative affectivity, sadness, and hostility.MethodSixty-seven adults diagnosed with depression were recruited from out-patient treatment settings (66% female, 81% White, M_age = 31, SD_age = 13.2). Participants completed measures on substance-related coping, depression, attributional style, and daily affect over a three-week period.ResultsSubstance use to cope predicted increases in depression among individuals with high-level internal attribution bias. Further, coping via substance use moderated the relationship between internal attribution bias and daily-level sadness, such that sadness was highest among individuals with a high internal attribution bias coupled with greater levels of coping via substance use. A modest, yet, non-significant upward trend in daily-level hostility was also observed.ConclusionsResults suggested that depressed individuals who habitually perceive themselves as being responsible or blameworthy for negative life events are at an increased risk of worsening depressive symptoms and experiencing greater daily levels of sadness over a relatively brief period of time, particularly, when tending to engage in substance use as a mechanism to cope. This interaction effect can elicit greater daily-level sadness as well. Findings may aid in the identification and treatment of individuals at risk of maintaining or worsening their depressive symptoms.     

Development of a twice daily dosing regimen of amoxicillin/clavulanate

Amoxicillin/clavulanate was first launched as a three times daily dosage for the treatment of a range of community-acquired infections. A decade later, it became necessary to introduce a twice daily dosage for reasons of convenience, compliance and to remain competitive with other recently launched antibacterials. Twice daily formulations of amoxicillin/clavulanate were developed in which the amount of amoxicillin was increased relative to clavulanate to provide equivalent bacteriological and clinical efficacy with no change in the safety profile. Equivalence of the two dosing regimens was confirmed by randomised clinical trials in adults (in skin and soft tissue, urinary tract and lower respiratory tract infections, sinusitis and recurrent tonsillitis) and paediatrics (in lower respiratory tract infections, otitis media and recurrent tonsillitis). An improvement in the safety profile, specifically gastrointestinal effects, due to the reduced daily dose of clavulanate, was noted for all patients, but particularly in children.     

Perspectives on patient-reported outcomes : content validity and qualitative research in a changing clinical trial environment

Patient-reported outcomes (PROs) represent the voice of the patient in drug and device evaluation. As such, the outcomes selected for evaluation must be relevant to the patient, and the instruments used to capture them must have sound measurement properties. This paper discusses the role of qualitative research methods in assuring PRO clarity and content validity in a clinical trial environment characterized by evolving regulatory policy, new advances in technology and increasingly diverse samples within global clinical trials. Three important PRO measurement issues influenced by these changes are addressed: (i) endpoint selection and instrument development; (ii) the adaptation of instruments for electronic administration; and (iii) conceptual equivalence of measures across diverse samples. These are viewed as interrelated issues of content validity that can be addressed through the appropriate and rigorous application of qualitative research methods. Focus groups, cognitive debriefing, user acceptance testing and translation methodologies are discussed as ways to address and document the content validity of PRO instruments and ensure the empirical data representing the voice of the patient is sound.     

Trauma exposure and heavy drinking and drug use among college students: Identifying the roles of negative and positive affect lability in a daily diary study

Trauma exposure is linked to heavy drinking and drug use among college students. Extant research reveals positive associations between negative affect lability and both trauma exposure and alcohol use. This study aimed to extend past research by using daily diary methods to test whether (a) individuals with (versus without) trauma exposure experience greater negative and positive affect lability, (b) negative and positive affect lability are associated with heavy drinking and drug use, and (c) negative and positive affect lability mediate the relations between trauma exposure and heavy drinking and drug use. Participants were 1640 college students (M age = 19.2, 54% female, 80% European American) who provided daily diary data for 30 days via online surveys. Daily diaries assessed negative and positive affect and substance use (i.e., percent days of heavy drinking, percent days of drug use, total number of drugs used). Individuals with (versus without) a history of trauma exposure demonstrated higher levels of negative and positive affect lability. Negative, but not positive, affect lability was associated with percent days of heavy drinking, percent days of drug use, and total number of drugs used, and mediated the associations between trauma exposure and heavy drinking and drug use outcomes. Findings provide support for the underlying role of negative affect lability in the relations between trauma exposure and heavy drinking and drug use among college students, suggesting that treatments targeting negative affect lability may potentially serve to reduce heavy drinking and drug use among trauma-exposed college students.     

The validity and reliability of the global index of safety (GIS)

Objective: The global index of safety (GIS) is an adverse event (AE) based instrument designed to evaluate the safety profile of drugs. This paper presents the evaluation of the inter-rater reliability and validity of a 94-item GIS for antipsychotics through Rasch analysis.

Research design and methods: A total of 194 psychiatrists participating in an outpatient pharmacoepidemiologic study of olanzapine in schizophrenia rated the severity that each AE would have on a 5-point scale. Reliability was

determined through a paired comparison design involving the new independent ratings of 101 different psychiatrists participating in another study of olanzapine in acute inpatient units. Spearman's, Pearson's and Intra-class correlation (ICC) coefficients were used to estimate the interrater reliability of the AE weights. Validity was analyzed through the Rasch rating scale model.

Results: Reliability coefficient estimates were excellent (Spearman = 0.99, Pearson = 0.99, ICC = 0.98), supporting the inter-rater reliability of the item weights. Through goodness-of-fit statistics and the investigation of the hierarchy of item calibrations, Rasch analysis confirmed the validity of the instrument.

Conclusion: The data presented here on interrater reliability estimates of adverse events related to antipsychotic drugs indicate that GIS is a promising alternative for the evaluation of the safety profile of drugs.     

The validity and reliability of the global index of safety (GIS)

OBJECTIVE: The global index of safety (GIS) is an adverse event (AE) based instrument designed to evaluate the safety profile of drugs. This paper presents the evaluation of the inter-rater reliability and validity of a 94-item GIS for antipsychotics through Rasch analysis. RESEARCH DESIGN AND METHODS: A total of 194 psychiatrists participating in an outpatient pharmacoepidemiologic study of olanzapine in schizophrenia rated the severity that each AE would have on a 5-point scale. Reliability was determined through a paired comparison design involving the new independent ratings of 101 different psychiatrists participating in another study of olanzapine in acute inpatient units. Spearman's, Pearson's and Intra-class correlation (ICC) coefficients were used to estimate the inter-rater reliability of the AE weights. Validity was analyzed through the Rasch rating scale model. RESULTS: Reliability coefficient estimates were excellent (Spearman = 0.99, Pearson = 0.99, ICC = 0.98), supporting the inter-rater reliability of the item weights. Through goodness-of-fit statistics and the investigation of the hierarchy of item calibrations, Rasch analysis confirmed the validity of the instrument. CONCLUSION: The data presented here on inter-rater reliability estimates of adverse events related to antipsychotic drugs indicate that GIS is a promising alternative for the evaluation of the safety profile of drugs.     

Lansoprazole 15 and 30 mg daily in maintaining healing and symptom relief in patients with reflux oesophagitis

Background: In patients with reflux oesophagitis, endoscopic healing and symptom relief are considered important treatment goals in long-term care.
Aim: To compare the effect of lansoprazole 15 and 30 mg daily on maintaining endoscopic healing and symptom relief in patients with moderate reflux oesophagitis.
Patients and methods: In a single-centre, double-blind randomized clinical trial, 103 patients with grade 1 or 2 reflux oesophagitis who were endoscopically healed and asymptomatic after lansoprazole 30 mg daily for 12 weeks, were randomized to maintenance therapy with either lansoprazole 15 mg or 30 mg o.m. Endoscopy was repeated after 3, 6 and 12 months, and symptom relief assessed after 3, 6, 9 and 12 months. Relapse of oesophagitis or symptoms were considered end-points.
Results: After 12 months, 14/50 patients (28%) receiving lansoprazole 15 mg daily had suffered an endoscopic relapse compared to 8/53 patients (15%) treated with lansoprazole 30 mg daily. A life table analysis showed no statistically significant difference between the two groups ( P =0.086). Significantly more patients were kept in complete symptomatic remission in the 30 mg group ( P <0.01). In the 15 mg group, 23/50 (46%) had suffered either an endoscopic or symptomatic relapse on completion of the study, compared to 12/53 (23%) in the 30 mg group. A life table analysis showed this difference to be statistically significant ( P =0.010). Lansoprazole 15 and 30 mg daily were equally well tolerated.
Conclusion: No statistically significant differences were found in endoscopic relapse rate or occurrence of adverse events, while lansoprazole 30 mg proved superior to 15 mg in maintaining patients in symptomatic relief and combined endoscopic and symptomatic remission.     

The role of coping in moderating within-day associations between negative triggers and substance use cravings: A daily diary investigation

To address the lack of research examining within-person processes associated with the maintenance of abstinence from substance use, this study examines both associations between negative affect and social experiences and same-day levels of substance use cravings among college students in ‘Twelve-Step’ substance abuse recovery and the role of coping strategies in moderating these within-day associations. The sample consisted of 1222 end-of-day reports made by 55 recovering college students, 39 males and 16 females. Findings include that daily cravings were predicted by same-day negative affect and each of four negative social experiences. Moreover, each of these within-day associations was moderated by individuals' levels of avoidance coping. In contrast, problem-solving coping only moderated the associations between negative affect and cravings. These findings document a within-day mechanism through which coping strategies, especially avoidance coping, may influence daily variation in cravings and in turn affect abstinence.     

Predictive validity of the tobacco marketing receptivity index among non-smoking youth

IntroductionIn a previous cross-sectional study of early adolescents, we developed a marketing receptivity index (MRI) that integrates point-of-sale (PoS) marketing exposures, brand recall, and ownership of branded merchandise. The MRI had independent, positive associations with smoking susceptibility among never smokers and with current smoking behavior. The current longitudinal study assessed the MRI's predictive validity among adolescents who have never smoked cigarettesMethodsData come from a longitudinal, school-based survey of 33 secondary schools in Argentina. Students who had never smoked at baseline were followed up approximately 17 months later (n = 1700). Questions assessed: PoS marketing exposure by querying frequency of going to stores where tobacco is commonly sold; cued recall of brand names for 3 cigarette packages from dominant brands but with the brand name removed; and ownership of branded merchandise. A four-level MRI was derived: 1.low PoS marketing exposure only; 2. high PoS exposure or recall of 1 brand; 3. recall of 2 or more brands; and 4. ownership of branded merchandise. Logistic regression models regressed smoking initiation by follow up survey on the MRI, each of its components, and students' willingness to try a brand, adjusting for sociodemographics, social network smoking, and sensation seeking.ResultsThe MRI had an independent positive association with smoking initiation. When analyzed separately, each MRI component was associated with outcomes except branded merchandise ownership.ConclusionsThe MRI and its components were associated with smoking initiation, except for branded merchandise ownership, which may better predict smoking progression than initiation. The MRI appears valid and useful for future studies.