Academic Procrastination State Inventory – German Version (APSI-d)

1. Abstract

The Academic Procrastination State Inventory – German Version (Academic Procrastination State Inventory – Deutsche Version, APSI-d) is an established psychometric assessment designed to capture situational, state-level manifestations of academic postponement behaviors, cognitive disruptions, and negative affective states among university students. Originating from the Dutch inventory developed by Henri C. Schouwenburg (1994, 1995) and subsequently translated, adapted, and standardized for German-speaking populations by Andreas Helmke and Friedrich-Wilhelm Schrader (2000), the instrument was comprehensively re-evaluated by Inga Opitz and Julia Patzelt (2004) at the University of Münster. Comprising 23 self-report items referenced to the respondent’s behaviors and cognitive-emotional experiences over the preceding week, the APSI-d operationalizes procrastination as a multi-determined dynamic state rather than a static personality trait.

Psychometric evaluation through categorical confirmatory factor analysis (CFA) confirms a robust three-factor multidimensional structure: (1) State-Procrastination in the Strict Sense (State-Prokrastination im engeren Sinne; 12 items), capturing core behavioral delay, distractibility, energy deficits, and competing pleasurable activities; (2) Fear and Insecurity (Angst und Unsicherheit; 6 items), assessing evaluative anxiety, panic symptoms, self-doubt, and tension during academic tasks; and (3) Aversion (Abneigung; 5 items), indexing resentment, boredom, and motivational alienation regarding study materials. Responses are recorded on a 5-point Likert-type frequency scale ranging from 1 (niemals / never) to 5 (immer/ständig / always/constantly). The APSI-d exhibits excellent internal consistency across all subdimensions, with Cronbach’s alpha coefficients ranging from .82 to .89. Convergent validity is evidenced through strong correlations with trait procrastination measures (r = .70) as well as substantial associations with depressive symptomatology (PHQ-D), failure anxiety, evaluation apprehension, and cognitive cognitive everyday slips (CFQ). Furthermore, intervention studies demonstrate high sensitivity to change following cognitive-behavioral time-management and self-regulation training, establishing the APSI-d as a vital instrument for academic counseling, psychological diagnostics, and intervention research.

2. Keywords

Academic Procrastination State Inventory, APSI-d, academic procrastination, state procrastination, self-regulation, task aversion, evaluation anxiety, psychometrics, confirmatory factor analysis, student mental health, learning behavior, higher education.

3. Authors

The development, adaptation, and psychometric validation of the APSI-d represent a collaborative progression across several prominent educational and clinical psychologists:

• Original Dutch Scale Developer: Henri C. Schouwenburg, Ph.D., Department of Psychology, University of Groningen, Netherlands. Primary developer of the foundational Academic Procrastination State Inventory (APSI, 1994, 1995).
• German Adaptation Authors: Andreas Helmke, Ph.D., and Friedrich-Wilhelm Schrader, Ph.D., Department of Educational Psychology, University of Koblenz-Landau (Campus Landau), Germany (2000).
• Large-Scale Validation and Psychometric Testing (University of Münster Cohort):
  • Julia Patzelt, Dipl.-Psych., Westfälische Wilhelms-Universität Münster, Psychotherapy Outpatient Clinic (Psychotherapie-Ambulanz), Fliednerstraße 21, Pavillon V, 48149 Münster, Germany. E-mail: [email protected]
  • Inga Opitz, Dipl.-Psych., Westfälische Wilhelms-Universität Münster, Institute of Psychology I (Psychological Assessment and Clinical Psychology), Münster, Germany. E-mail: [email protected]
  • Collaborating intervention researchers: Eva-Maria Beißner and Astrid Samberg (2004), Westfälische Wilhelms-Universität Münster.

4. Purpose

Academic procrastination represents one of the most pervasive self-regulatory vulnerabilities in tertiary education, afflicting between 50% and 80% of university students at clinically or functionally impairing levels. Defined broadly as the voluntary delay of an intended and necessary course of action despite anticipating that one will be worse off for the delay, academic procrastination compromises academic performance, escalates scholastic attrition, and serves as a major risk factor for acute psychological distress, including depressive mood states, somatic anxiety, and pervasive feelings of guilt. Although numerous assessment tools conceptualize procrastination as a stable, cross-situational personality trait (e.g., the Aitken Procrastination Scale; Lay’s General Procrastination Scale), such trait instruments are structurally ill-suited for capturing micro-level behavioral fluctuations, contextual academic demands, or short-term therapeutic changes.

The primary purpose of the Academic Procrastination State Inventory – German Version (APSI-d) is to provide a precise, sensitive, and multidimensional measurement tool capable of evaluating procrastination as a dynamic, situation-dependent behavioral state. By anchoring all items to the respondent’s concrete study behaviors and cognitive-affective experiences during the preceding week (“in der letzten Woche”), the APSI-d bridges the gap between ultra-brief momentary state assessments and broad, decontextualized dispositional scales. This specific retrospective one-week window enables students and researchers to capture meaningful behavioral episodes—such as preparing for a specific written examination, drafting a seminar term paper, or completing weekly course assignments—without losing temporal precision.

In applied academic counseling, university psychological services, and psychotherapeutic clinics, the APSI-d serves three essential diagnostic and clinical functions:

• Diagnostic Differentiation: The tool unpacks the heterogeneous etiology of a student’s dilatory behavior by distinguishing whether the primary driver is executive dysfunction and impulse control (State Procrastination in the strict sense), neurotic evaluation apprehension and panic (Fear and Insecurity), or motivational depletion and academic alienation (Aversion).
• Treatment Planning and Personalization: Counseling interventions can be custom-tailored based on subscale profiles. Students scoring high on core behavioral delay benefit most from stimulus control, habit training, and time-structuring modules, whereas those characterized by high anxiety require cognitive restructuring of failure expectations, and those high in aversion require motivational reframing or curricular realignment.
• Evaluation of Interventions and Process Tracking: Because of its one-week state format, the APSI-d is ideally configured for pre-post intervention studies, session-by-session monitoring, and longitudinal time-series analyses aimed at tracking the efficacy of cognitive-behavioral group trainings or digital self-help interventions.

5. Psychological Construct

The construct operationalized by the APSI-d is academic state procrastination, conceptualized as a multi-component syndrome involving behavioral, affective, and cognitive elements. While early conceptualizations treated procrastination merely as poor time management or an indolent lifestyle choice, contemporary psychometrics regards it as a complex failure of volitional self-regulation under conditions of perceived task difficulty, threat, or boredom. Helmke and Schrader (2000), followed by Opitz (2004) and Patzelt (2004), established that the APSI-d encompasses three distinct yet intercorrelated latent dimensions:

Subdimension I: State Procrastination in the Strict Sense (State-Prokrastination im engeren Sinne)

Comprising 12 items (Items 1, 2, 3, 4, 5, 6, 7, 9, 10 reversed, 11, 12, and 23), this subdimension forms the behavioral and executive core of the procrastination construct. It quantifies the gap between intention and action—frequently termed the “intention-action gap” in action control theory. Manifest indicators assess:

• Premature task cessation and preference for competing pleasant activities: Terminating study sessions early to indulge in short-term hedonic gratifications (e.g., socializing, multimedia consumption; Item 1).
• Task interruption and distractibility: Suspending work to engage in alternate tasks or succumbing to internal and external distractions (Items 2, 3, and 12).
• Postponement of task completion: Deferring finalization and repeatedly revising completion timelines (Item 4).
• Anergia and low volitional energy: Experiencing a subjective sense of mental fatigue or physical inertia when facing study materials (Item 5).
• Initiation paralysis: Resolving to begin studying at a pre-set hour but failing to enact the behavioral initiation (Item 6).
• Cognitive rationalizations and temporal discounting: Generating irrational cognitive justifications, such as believing there is plenty of time left to delay initial work (Item 11).
• Preparatory neglect: Forgetting or failing to organize the materials, textbooks, or software needed to study (Item 23).

Subdimension II: Fear and Insecurity (Angst und Unsicherheit)

Encompassing 6 items (Items 8, 13, 14, 15, 16, and 17), this subdimension captures the affective distress and evaluative vulnerability that frequently accompany or trigger avoidance behavior. Procrastination is recognized not as an absence of concern, but rather as an emotion-focused coping strategy designed to short-circuit acute ego threat. The items assess:

• Cognitive disruption under emotional distress: Attentional wandering and concentration deficits during study activities (Item 8).
• Somatic and psychovegetative tension: Experiencing pronounced muscular and mental tension or somatic discomfort leading to abandonment of study sessions (Items 13 and 17).
• Acute panic reactions: Subjective feelings of panic and acute cognitive overwhelm during engagement with course materials (Item 14).
• Evaluation and failure anxiety: Persistent dread of failing to satisfy academic standards, course requirements, or parental and faculty expectations (Item 15).
• Imposter feelings and competence doubt: Severe doubts regarding one’s cognitive and intellectual capabilities (Item 16).

Subdimension III: Aversion (Abneigung)

Comprising 5 items (Items 18, 19, 20, 21, and 22), this dimension measures motivational estrangement, boredom, and negative valence toward academic work. Task aversiveness has consistently emerged as one of the strongest predictive determinants of task avoidance in behavioral economics and motivational psychology. Indicators include:

• Intense negative affect toward studying: Feelings approaching genuine resentment or hatred toward academic labor (Item 18).
• Existential educational questioning: Cynical contemplation regarding the overall value of tertiary studies when accompanied by chronic vexation and distress (Item 19).
• Specific curricular aversion: Deep distaste or repulsion toward the particular subject matter being learned (Item 20).
• Curricular regret: Doubting the decision to enroll in the academic program or specific course offerings (Item 21).
• Monotony and boredom: Finding learning materials inherently unstimulating and tedious (Item 22).

6. Theoretical Framework

The theoretical architecture of the APSI-d is grounded in several converging paradigms within modern educational, cognitive-behavioral, and self-regulatory psychology, most notably Temporal Motivation Theory (TMT; Steel, 2007), Self-Regulation Theory (Baumeister & Heatherton, 1996), and the behavioral manifestation framework of Schouwenburg (1995).

Schouwenburg (1995) conceptualized academic procrastination through three primary behavioral indicators: (a) a lack of promptness or timeliness in both intention formation and behavioral execution, (b) a systematic discrepancy between intentions and realized behavior, and (c) an overt preference for competing, hedonically appealing alternative activities. While early research treated procrastination as non-problematic everyday delay (Schouwenburg, 1992), influential clinical frameworks by Solomon and Rothblum (1984) redefined procrastination as an inherently dysfunctional pattern: “the act of needlessly delaying tasks to the point of experiencing subjective discomfort” (p. 503). The APSI-d explicitly incorporates this clinical perspective by pairing behavioral delay items with indicators of subjective distress, negative affect, and operational impairment.

From the perspective of Temporal Motivation Theory, procrastination is modeled through the interaction of Expectancy, Value, Impulsiveness, and Delay:$$\text{Utility} = \frac{\text{Expectancy} \times \text{Value}}{\Gamma + \text{Impulsiveness} \times \text{Delay}}$$Within this mathematical formulation:

• Expectancy (self-efficacy and perceived probability of success) is directly reflected in the APSI-d’s Fear and Insecurity dimension. When students doubt their capabilities (Item 16) or fear failing expectations (Item 15), expectancy plummets, reducing overall task utility and precipitating avoidance.
• Value (task valence and perceived intrinsic reward) corresponds directly to the APSI-d’s Aversion dimension. When studying is perceived as boring (Item 22) or hateful (Item 18), task utility approaches zero.
• Delay and Impulsiveness correspond to the State Procrastination in the Strict Sense dimension, where temporal discounting causes distal study deadlines to lose utility compared to immediate, pleasurable temptations (Items 1 and 11).

Furthermore, the instrument incorporates Julius Kuhl’s Action Control Theory (Handlungskontrolltheorie). Kuhl distinguished between action orientation (the capacity to initiate and sustain goal-directed intentions under stress) and state orientation (a ruminative fixation on past failures, affective tension, and hesitation). The APSI-d serves as an empirical operationalization of an acute state-oriented breakdown: when faced with complex, ill-defined academic challenges, individuals slip into rumination, attentional lapses (Item 12), and paralysis (Item 6), resulting in volitional failure.

7. Validity

The validity of the APSI-d has been substantiated through extensive empirical investigations involving diverse student samples, multi-trait multi-method comparisons, and clinical intervention trials.

Construct and Convergent Validity

In a large-scale psychometric investigation conducted at the Westfälische Wilhelms-Universität Münster by Opitz (2004) and Patzelt (2004) comprising $N = 939$ matriculated students (50.3% male, 49.7% female; mean age 23.0 years across 45 academic disciplines), the APSI-d was administered alongside the German Aitken Procrastination Scale (APS-d; a trait measure) and standardized batteries for psychopathology, anxiety, and cognition:

• Convergence with Trait Procrastination: The APSI-d Subdimension 1 (State-Procrastination i.e.S.) demonstrated a strong positive correlation ($r = .70$) with the primary subscale of the APS-d (Central Procrastination), establishing that situational delay corresponds robustly to habitual delay patterns while retaining situational variance.
• Association with Depressive Symptoms: Subdimension 1 ($r = .42$), Subdimension 2 ($r = .39$), and Subdimension 3 ($r = .35$) correlated moderately and significantly with depression as assessed by the Patient Health Questionnaire – Depression Module (PHQ-D), validating the clinical conceptualization of procrastination as a psychologically distressing phenomenon.
• Anxiety and Evaluative Concerns: The Fear and Insecurity subscale exhibited pronounced positive correlations with Fear of Failure (Leistungshindernde Angst, LHA; $r = .35$) and Social Evaluative Anxiety (Soziale Angst vor negativer Bewertung, SANB; $r = .20$).
• Cognitive Failures: All three APSI-d subscales demonstrated moderate correlations ($r = .40$, $.23$, and $.27$, respectively) with everyday cognitive slips and executive lapses measured by the Cognitive Failures Questionnaire (CFQ).

Discriminant Validity

Correlations with perfectionism scales (Frost Multidimensional Perfectionism Scale, MPS) revealed that self-oriented perfectionism (MPS-1) had negligible to weak negative correlations with state procrastination ($r = -.16$ to $-.22$), whereas socially prescribed perfectionism (MPS-2) exhibited weak associations ($r = .04$ to $.18$). This confirms that academic state procrastination is psychometrically distinguishable from high personal performance standards.

Known-Groups and Differential Validity

The Münster validation study demonstrated that the APSI-d sensitively differentiates between sociodemographic and academic subgroups:

• Gender Differences: Female students scored significantly higher on Fear and Insecurity ($M = 1.63, SD = 0.73$) than male students ($M = 1.34, SD = 0.75; p < .001, d = 0.39$), mirroring established epidemiological findings regarding female evaluation anxiety. In contrast, no significant gender differences emerged for core state delay ($p = .14$) or aversion ($p = .10$).
• Academic Progression: Students in advanced semesters (Semesters 7–17; $M = 2.03, SD = 0.65$) exhibited significantly higher core state procrastination than mid-level students (Semesters 4–6; $M = 1.84, SD = 0.65; p = .002, d = 0.29$), reflecting the loss of external structure in thesis preparation and comprehensive examination phases.
• Curricular Structure: Students in loosely structured degree courses (e.g., cultural studies, political sciences) exhibited significantly higher overall APSI-d scores ($M = 1.78, SD = 0.57$) and core state delay ($M = 2.07, SD = 0.65$) than students in highly structured disciplines (e.g., medicine, psychology; Overall: $M = 1.61, SD = 0.56, p = .005, d = 0.30$; Core Delay: $M = 1.81, SD = 0.66, p < .001, d = 0.40$).

Criterion and Longitudinal Sensitivity to Intervention

Criterion-related validity was further established in a clinical intervention study (Beißner, 2004; Samberg, 2004) evaluating a targeted cognitive-behavioral group intervention ($N = 56$ procrastinating students) focused on punctual study initiation and realistic calendar planning. Baseline APSI-d scores of self-referred participants were more than one full standard deviation above the general student norm. Following the intervention, post-training APSI-d scores decreased significantly and were no longer statistically distinguishable from the non-clinical student population, confirming that the APSI-d possesses high treatment sensitivity.

8. Reliability

The APSI-d possesses robust internal consistency across all three subscales, well exceeding standard psychometric benchmarks for psychological diagnostic inventories in applied research and individual assessment.

Internal Consistency (Cronbach’s Alpha)

In the primary Münster validation sample ($N = 939$), internal consistencies were computed using Cronbach’s alpha coefficients:

• Subdimension I (State Procrastination i.e.S.): $\alpha = .89$ (12 items). Corrected item-total correlations ranged from $.51$ to $.73$, indicating exceptional homogeneity. Deletion of any individual item resulted in alpha values between $.87$ and $.89$, confirming that every item contributes meaningfully to the latent behavioral delay construct.
• Subdimension II (Fear and Insecurity): $\alpha = .83$ (6 items). Alpha if item deleted ranged between $.79$ and $.85$. Items assessing panicky feelings (Item 14) and failure anxiety (Item 15) demonstrated the highest item-total correlations.
• Subdimension III (Aversion): $\alpha = .82$ (5 items). Alpha if item deleted ranged between $.77$ and $.81$. Items measuring specific subject aversion (Item 20) and study resentment (Item 18) displayed strong discrimination.

Item Distributional Characteristics

Table 1 summarizes the descriptive statistics, skewness, kurtosis, and internal consistency parameters from the large-scale Münster sample ($N = 939$):

9. Factor Analysis

The factorial validity of the APSI-d has undergone rigorous developmental and confirmatory testing across two primary iterations: exploratory factor modeling by Helmke and Schrader (2000) and confirmatory structural modeling for categorical data by Opitz (2004) and Patzelt (2004).

Exploratory Factor Analysis (Helmke & Schrader, 2000)

In the initial German validation, Helmke and Schrader conducted principal component analyses with varimax rotation. They extracted three primary factors accounting for 59.8% of the total cumulative variance in item responses. They interpreted these factors as: (1) Procrastination in the strict sense (delaying, concentration problems, anergia), (2) Fear of Failure, and (3) Motivational Deficits (aversion).

Categorical Confirmatory Factor Analysis (Münster Validation)

Because item responses on 5-point frequency scales frequently exhibit positive skewness and categorical measurement properties in non-clinical student populations, Opitz (2004) and Patzelt (2004) executed Confirmatory Factor Analysis (CFA) using Mplus with robust weighted least squares estimators designed for ordered categorical indicators (WLSMV).

The three-factor theoretical model demonstrated an acceptable to good fit to the empirical data after incorporating specific cross-loadings and residual covariances:

• Chi-Square Fit Statistic: $\chi^2 = 502.94$ with degrees of freedom $df = 105$ ($p < .001$).
• Comparative Fit Index (CFI): $\text{CFI} = 0.93$.
• Tucker-Lewis Index (TLI): $\text{TLI} = 0.98$.
• Root Mean Square Error of Approximation (RMSEA): $\text{RMSEA} = 0.06$ ($90%\text{ CI } [0.054, 0.066]$), indicating close approximate model fit.

Factor Loadings and Modifications

Standardized factor loadings across the items ranged from $lambda = .26$ to $.93$ (all $p < .001$):

• Factor 1 (State Procrastination i.e.S.): Items measuring behavioral delay and distraction exhibited strong loadings, including Item 4 ($lambda = .79$), Item 6 ($lambda = .78$), Item 2 ($lambda = .74$), Item 3 ($lambda = .73$), and Item 1 ($lambda = .72$). Reversed Item 10 loaded moderately at $lambda = -.52$.
• Factor 2 (Fear and Insecurity): Highest loadings emerged for Item 16 (doubts in abilities, $lambda = .86$), Item 15 (fear of demands, $lambda = .84$), and Item 14 (panic feelings, $lambda = .79$).
• Factor 3 (Aversion): Prominent loadings were observed for Item 20 (dislike of learning material, $lambda = .88$), Item 18 (hatred toward study, $lambda = .82$), and Item 19 (questioning study purpose, $lambda = .79$).

Psychometric refinement revealed several cross-loadings reflecting shared underlying psychological mechanisms: Item 5 (energy deficit), Item 8 (concentration problems), Item 13 (quitting due to feeling unwell), and Item 23 (failure to prepare) showed significant associations across two factors. Specifically, concentration difficulties and low energy span both executive self-regulatory breakdown and somatic stress reactions. Furthermore, Items 18 and 19—which Helmke and Schrader originally mapped to fear of failure—loaded unequivocally onto the Aversion factor in the Münster analysis, reflecting existential resentment rather than anxiety per se. Inter-factor correlations ranged between $r = .30$ and $.67$, demonstrating that while the dimensions share substantial variance under the overarching procrastination umbrella, they represent distinct psychological processes.

10. Instrument / Measurement Tool

The APSI-d is presented as a standardized, self-administered questionnaire. Its formal administration characteristics are structured as follows:

• Instrument Name: Academic Procrastination State Inventory – Deutsche Version (APSI-d)
• Target Population: Undergraduate, graduate, and post-graduate university students; adaptable for secondary school students in upper gymnasium tracks.
• Measurement Paradigm: Situational state questionnaire referencing learning behavior over a defined retrospective period (the past 7 days).
• Item Count: 23 items organized across three distinct subscales.
• Administration Modality: Available in paper-and-pencil format or as an online interactive digital assessment.
• Estimated Completion Time: 5 to 8 minutes.
• Response Format: 5-point Likert-type frequency scale with the following response anchors:
  • 1 = niemals (never)
  • 2 = selten (rarely)
  • 3 = manchmal (sometimes)
  • 4 = meistens (mostly)
  • 5 = immer/ständig (always/constantly)
• Scoring and Transformation Rules:
  • Reverse Scoring: Item 10 is positively phrased (“auch tatsächlich den Stoff gelernt, den Sie sich vorgenommen hatten”) and must be reverse-coded prior to subscale or composite score aggregation: $\text{Item } 10_{\text{recoded}} = 6 – \text{Raw Score}$ (or $4 – X$ if coded 0–4).
  • Subscale Mean Computation:
    • Subdimension I (State Procrastination i.e.S.): Sum or mean of Items 1, 2, 3, 4, 5, 6, 7, 9, 10 (reversed), 11, 12, 23 (divided by 12).
    • Subdimension II (Fear and Insecurity): Sum or mean of Items 8, 13, 14, 15, 16, 17 (divided by 6).
    • Subdimension III (Aversion): Sum or mean of Items 18, 19, 20, 21, 22 (divided by 5).
  • Composite Procrastination Score: An overarching state procrastination index can be generated by calculating the mean across all 23 items. Higher values reflect greater severity of state-level academic procrastination.
  • Normative Reference Data: Population-representative percentile norms have not been published; evaluation typically utilizes the mean and standard deviation benchmarks from the Münster university cohort ($N = 939$) or within-subject baseline comparisons in intervention contexts.

11. Permissions & Fee and Test Year

The academic development and validation history of the APSI-d spans several milestones:

• Year of Original Foundation: 1994, 1995 (Henri C. Schouwenburg, University of Groningen).
• Year of German Translation and Publication: 2000 (Andreas Helmke & Friedrich-Wilhelm Schrader, University of Koblenz-Landau).
• Year of Psychometric Standardization: 2004 (Inga Opitz & Julia Patzelt, Westfälische Wilhelms-Universität Münster).
• Copyright and Repository Status: The German version of the instrument is documented in the open-access psychometric repository GESIS ZIS (Zusammenstellung sozialwissenschaftlicher Items und Skalen).
• Usage Permissions: The APSI-d is an open-access scientific instrument. It is freely accessible for non-commercial academic research, pedagogical investigations, university counseling evaluations, and clinical training. Researchers and clinicians utilizing the inventory are requested to cite the foundational validation publications (Helmke & Schrader, 2000; Opitz, 2004; Patzelt, 2004). Commercial utilization or integration into proprietary software suites requires formal consultation and written authorization from the primary authors.

12. References

Below is the academic bibliography underpinning the APSI-d and its psychometric validation (in APA 7th edition format):

• Baumeister, R. F., & Heatherton, T. F. (1996). Self-regulation failure: An overview. Psychological Inquiry, 7(1), 1–15. https://doi.org/10.1207/s15327965pli0701_1
• Beißner, E.-M. (2004). Entwicklung und Evaluation eines kognitiv-behavioralen Trainings zur Reduktion von Prokrastination bei Studierenden [Unpublished diploma thesis]. Westfälische Wilhelms-Universität Münster.
• Ferrari, J. R., Johnson, J. L., & McCown, W. G. (1995). Procrastination and task avoidance: Theory, research, and treatment. Springer Science+Business Media. https://doi.org/10.1007/978-1-4899-0227-6
• Helmke, A., & Schrader, F.-W. (2000). Prokrastination im Studium: Erscheinungsformen und motivationale Bedingungen [Procrastination in higher education: Manifestations and motivational conditions]. In U. Schiefele & K.-P. Wild (Eds.), Interesse und Motivation im Studium (pp. 207–225). Waxmann.
• Kuhl, J. (1992). A theory of self-regulation: Action versus state orientation, self-discrimination, and some applications. Applied Psychology, 41(2), 97–129. https://doi.org/10.1111/j.1464-0597.1992.tb00688.x
• Opitz, I. (2004). Validierung von Verfahren zur Erfassung von Prokrastination [Unpublished diploma thesis]. Westfälische Wilhelms-Universität Münster.
• Patzelt, J. (2004). Psychometrische Überprüfung von Verfahren zur Erfassung von Prokrastination [Unpublished diploma thesis]. Westfälische Wilhelms-Universität Münster.
• Samberg, A. (2004). Evaluation eines Gruppentrainings gegen Aufschiebeverhalten bei Studierenden [Unpublished diploma thesis]. Westfälische Wilhelms-Universität Münster.
• Schouwenburg, H. C. (1994). Academic Procrastination State Inventory (APSI) [Unpublished research instrument]. Department of Psychology, University of Groningen.
• Schouwenburg, H. C. (1995). Academic procrastination: Theoretical notions, measurement, and research. In J. R. Ferrari, J. L. Johnson, & W. G. McCown (Eds.), Procrastination and task avoidance: Theory, research, and treatment (pp. 71–96). Springer. https://doi.org/10.1007/978-1-4899-0227-6_4
• Solomon, L. J., & Rothblum, E. D. (1984). Academic procrastination: Frequency and cognitive-behavioral correlates. Journal of Counseling Psychology, 31(4), 503–509. https://doi.org/10.1037/0022-0167.31.4.503
• Steel, P. (2007). The nature of procrastination: A meta-analytic and theoretical review of quintessential self-regulatory failure. Psychological Bulletin, 133(1), 65–94. https://doi.org/10.1037/0033-2909.133.1.65
• Tuckman, B. W. (1991). The development and concurrent validity of the Procrastination Scale. Educational and Psychological Measurement, 51(2), 473–480. https://doi.org/10.1177/0013164491512022

13. Items of the Scale (Questionnaire)