Many substance users deny their substance use to avoid negative consequences, thus diluting the accuracy of assessment. To address this issue, indirect items are often included on substance use measures to identify those who deny their use. The purpose of this study was to examine the effect of complete denial and partial denial on substance use measures. Partial denial, also termed denial of effects, is the denial of substance use interfering in multiple domains of a person's functioning. The study used a mixed within- and between-subjects design with participants from a dual diagnosis inpatient unit. Each participant completed the study under two different conditions which include an honest condition and an experimental condition (either complete denial or partial denial). Results show that partial denial is distinctly different from complete denial across three self-report substance use measures. Importantly, substance users engaging in these denial conditions were often undetected by these measures.

The Substance Abuse Subtle Screening Inventory (SASSI) is a 10 scale indirect screening instrument used to detect substance use disorders. The current meta-analytic study described reliability reporting practices across 48 studies involving the SASSI. Reliability generalization methods were then employed to evaluate typical score reliability for the screening measure. Results showed approximately 73 of studies did not report reliability estimates. Analysis of data from the remaining studies revealed adequate reliability for the total scale (α .87) and face valid scales (FVA α .88 and FVOD α .92), but substantially lower reliability estimates for the indirect scales (range of α .23.65). The study's findings underscore the need for improved reliability reporting for the SASSI and suggest cautious use of the measure, especially its indirect scales, as an indicator of problematic substance use/abuse in clinical settings.

The fundamental principle that reliability is a property of scores and not of instruments provides the foundation of a meta-analytic technique called reliability generalization (RG). RG studies characterize the reliability of scores generated by a given instrument and identify methodological and sample characteristics that contribute to the variability in the reliability of those scores. The present study is an RG of the Substance Abuse Subtle Screening Inventory (SASSI). Reliability estimates were obtained from 19.8% of studies using the SASSI. Bivariate correlations revealed strong, positive correlations between SASSI score reliability and score variability of the Subtle Attributes (r = .877, p < .05) and Family History (r = .892, p < .05) subscales and between score reliability and ethnicity for both the Family History (r = .683, p < .05) and Tendency to Involvement in Correctional Setting (r = .76, p < .05) subscales.

Every airlines maintenance programme is based on the maintenance task thresholds and Repeat Intervals. TUIfly Nordic’s technical department has experienced that some or no consideration has been given to the various maintenance task intervals in relation to the area of the aircraft and the access requirements for performing a maintenance task. Accordingly, we have been assigned by TUIfly Nordic to investigate whether an optimization of the maintenance programme for the B737NG fleet is possible, by taking the area and access requirements of the plane into account. As a direct result of how current maintenance programme is constructed, tasks conducted on a specific area of the aircraft are not coordinated, which means that opening/removal of panels/doors are made too often, therefore costing a lot of time and money. The purpose of the thesis was to identify possible adjustments in the intervals to coordinate the maintenance tasks by area and access requirements. TUIfly Nordic's concerns regarding their maintenance programme have been studied through data collection and analysis from various literature studies, especially from the company's and the manufacturer's manuals. A compilation of 41 maintenance tasks in seven areas has been presented where de-escalation in threshold is an option to schedule maintenance tasks that occur in the same area and access requirements. The result that is presented is only a concept and can therefore not be used directly into the maintenance programme, without an evaluation made by TUIfly Nordic’s technical department. The final outcome of this thesis is a recommendation on how to best optimize a maintenance programme for B737NG, in the matter of taking the area and access requirements of the plane into account, which was the objective and desired outcome of the work. / Idag bygger varje flygbolag sitt underhållsprogram baserat på underhållsåtgärdernas tröskelvärden och Repeat intervall. TUIfly Nordics tekniska avdelning har upplevt att liten eller ingen hänsyn har tagits till de olika underhållsåtgärdernas intervall i relation till område på flygplan och åtkomstkrav för att utföra en underhållsåtgärd. Med anledning av detta har vi för detta arbete fått i uppdrag av TUIfly Nordic att utreda huruvida en optimering av underhållsprogrammet för B737NG flottan är möjlig, genom att ta hänsyn till område och åtkomstkrav på planet. Konsekvensen av dagens underhållsprogram är att åtgärder med samma åtkomstkrav ej samordnas. D.v.s. öppning/borttagning av paneler/luckor görs för ofta, vilket kostar bolaget mycket tid och pengar. Målet med examensarbetet har varit att identifiera möjliga justeringar i intervall för att planera underhållsåtgärder efter område och åtkomstkrav, så att de görs samtidigt. Genom en datainsamling och analys från diverse litteraturstudier, bolagets och tillverkarens manualer, har TUIfly Nordics problemställning kunnat utredas. En sammanställning av totalt 41 underhållsåtgärder i sju olika områden har redovisats, där en de-eskalering av tröskelvärde är ett alternativ för att samordna underhållsåtgärder som har samma område och åtkomstkrav. Resultatet som presenterats är endast ett koncept och kan därför inte användas direkt, utan en egen utvärdering av TUIfly Nordics tekniska avdelning. Kontentan av detta examensarbete är en rekommendation på hur man lämpligast optimerar ett underhållsprogram för B737NG medtaget hänsyn till område och åtkomstkrav, vilket var målsättningen och det önskade resultatet med arbetet.