Abstract
The Hurlbert Index of Sexual Excitability (HISE) is a premier 25-item self-report psychometric instrument designed to measure an individual's capacity for sexual arousal, ease of subjective and physiological excitation, and stability of sexual responsiveness across diverse erotic contexts. Developed by David F. Hurlbert, Carol Apt, and S. Michael Rabehl in 1993, the scale was created to address a critical diagnostic and theoretical gap in clinical sexology and marital therapy: the empirical separation of subjective sexual arousal and excitability from global sexual satisfaction, general desire, and orgasm consistency. The instrument utilizes a five-point response format ranging from 0 ("all of the time") to 4 ("never"), yielding a continuous composite score between 0 and 100, where higher scores reflect greater sexual excitability following appropriate reverse-scoring of items. Psychometric evaluations across clinical, community, and marital samples consistently demonstrate outstanding internal consistency, with Cronbach's alpha coefficients routinely exceeding .90, alongside robust test-retest reliability ($r > .85$) across multi-week intervals. Construct validity is supported by significant convergent correlations with measures of sexual assertiveness, sexual desire, and orgasmic capacity, and discriminant validity is confirmed through distinct divergent profiles against general marital maladjustment and affective distress. Structural analyses indicate a robust primary factor representing general sexual excitability, supplemented by discernible facets covering arousal latency, responsiveness to partner stimulation, cognitive-fantasy arousal, and maintenance of sexual excitement. This article provides a comprehensive academic analysis of the HISE, outlining its purpose, theoretical foundations, psychometric validity, reliability metrics, factor structure, administrative guidelines, and complete authentic scale items.
Keywords
Hurlbert Index of Sexual Excitability, HISE, sexual arousal, psychometrics, sexology, sexual dysfunction, sexual excitation, female sexual response, dual control model, clinical assessment, marital therapy, construct validity, test-retest reliability
Authors
The Hurlbert Index of Sexual Excitability was conceptualized, operationalized, and validated by a multidisciplinary team of clinicians and researchers in behavioral health, clinical psychology, and marital therapy:
- David F. Hurlbert, Ph.D.: Principal investigator, psychosexual researcher, and clinical sexologist formerly affiliated with the United States Department of Health and Human Services (Administration for Children and Families) and private clinical sexology practice in Atlanta/Roswell, Georgia, USA. Primary corresponding author for the Hurlbert sexual indices family (including the Hurlbert Index of Sexual Assertiveness and the Hurlbert Index of Sexual Desire).
- Carol Apt, Ph.D.: Medical sociologist, sexologist, and Professor of Sociology at South Carolina State University, Orangeburg, South Carolina, USA. Noted for empirical investigations into human sexuality, marital dynamics, and female sexual health.
- S. Michael Rabehl, Ph.D.: Research methodologist, statistician, and psychometrician specializing in behavioral outcome measurement and clinical research design.
Purpose
The primary purpose of the Hurlbert Index of Sexual Excitability (HISE) is to provide an objective, clinically sensitive, and psychometrically sound assessment of an individual's sexual excitability. In clinical sexology and couple psychotherapy, sexual difficulties are frequently conflated under undifferentiated labels such as "sexual dissatisfaction" or "sexual dysfunction." Historically, diagnostic frameworks such as the Diagnostic and Statistical Manual of Mental Disorders (DSM) categorized sexual disorders into discrete phases based on linear models—primarily desire, arousal, orgasm, and resolution. However, clinicians often lacked specific, standardized rating scales capable of isolating sexual arousal readiness and sustained excitability from upstream motivational states (such as libido or hypoactive sexual desire) and downstream neurophysiological events (such as orgasmic release).
Hurlbert, Apt, and Rabehl (1993) introduced the HISE to address these empirical challenges, specifically aiming to:
- Differentiate Arousal from Desire and Orgasm: The HISE isolates the cognitive, affective, and physical propensity to become sexually aroused in response to erotic stimulation, separating these dynamics from mere sexual interest or frequency of climax.
- Evaluate Latency and Maintenance: A significant proportion of sexual complaints, particularly among women experiencing sexual arousal difficulties, involve prolonged arousal latency or the rapid decay of excitement prior to completion of the sexual interaction. The HISE captures both initiation speed and the stability of excitement.
- Facilitate Differential Diagnosis: In clinical environments, the HISE assists practitioners in distinguishing between Female Sexual Arousal Disorder (FSAD), Female Orgasmic Disorder (FOD), Hypoactive Sexual Desire Disorder (HSDD), and secondary sexual distress stemming from marital or relational conflict.
- Measure Treatment Efficacy: The continuous scoring system of the HISE makes it an ideal instrument for tracking longitudinal outcomes in psychosexual counseling, cognitive-behavioral sex therapy, sensate focus interventions, and pharmacotherapeutic clinical trials evaluating pro-sexual agents.
- Support Cross-Sectional and Epidemiological Research: In social and sexological research, the HISE provides an empirical baseline to study how sexual excitability interacts with aging, relationship longevity, hormonal changes, neurobiology, and psychological wellbeing in both clinical and community cohorts.
Psychological Construct
The psychological construct assessed by the HISE is sexual excitability, defined as the individual's threshold for, subjective appraisal of, and physiological ease in generating and maintaining sexual arousal in response to a spectrum of erotic, tactile, imaginative, and interpersonal stimuli. Within modern sexological theory, sexual excitability is conceptualized not merely as a mechanical autonomic reflex, but as a complex multidimensional biopsychosocial state combining cognitive-affective processing, sensory receptivity, and genital vascular engorgement.
The HISE operationalizes this construct across several interrelated dimensions embedded within its 25 items:
1. Subjective Arousal Ease and Receptivity
This core dimension evaluates how readily an individual transitions from an unaroused state into a state of sexual activation upon exposure to sexual cues. Items probing this dimension assess the degree to which an individual experiences internal resistance or friction when attempting to engage sexually (e.g., assessing feelings that it is difficult or hard to become sexually excited, or experiencing low general excitement).
2. Arousal Latency and Temporal Dynamics
Arousal is intrinsically time-dependent. The HISE measures an individual's subjective perception of their own arousal timeline. It evaluates whether the respondent perceives that they require an inordinate amount of time to reach excitation relative to their expectations or the pace of the sexual encounter, identifying patterns where individuals report taking "too long" to become aroused.
3. Maintenance and Lability of Arousal
A central feature of sexual excitement is its vulnerability to disruption. Cognitive distractions, performance anxiety, fatigue, or abrupt transitions during intimacy can extinguish autonomic arousal. The HISE incorporates specific items evaluating whether an individual can sustain their arousal throughout foreplay and intercourse or whether they experience premature arousal decay.
4. Stimulus-Specific Erotic Responsiveness
Human sexual excitability is triggered through diverse sensory and psychological pathways. The HISE captures responsiveness across several specific behavioral and mental domains:
- Tactile and Partner Sensations: Responsiveness to kissing, partner touch, foreplay, and specific sexual behaviors such as oral sex (both receiving and providing) and sexual intercourse.
- Cognitive-Imaginative Stimulation: Responsiveness to mental stimuli, including sexual fantasies, erotic thoughts, and anticipatory excitement.
- Solitary Arousal Capacity: Responsiveness to masturbation, which isolates individual physiological excitability from partner-dependent relational variables.
- Altruistic/Mutual Eroticism: Sexual arousal derived from providing sexual pleasure to a partner, reflecting the interpersonal reciprocity of erotic responsiveness.
Theoretical Framework
The Hurlbert Index of Sexual Excitability is anchored in prominent neurobiological and cognitive models of human sexual response developed over the past half-century. Its design bridges early linear physiological models with modern cognitive-affective and dual-process theories.
The Masters and Johnson Linear Paradigm
Early psychosexual assessment relied heavily on the classic four-phase human sexual response cycle formulated by William H. Masters and Virginia E. Johnson (1966): Excitement, Plateau, Orgasm, and Resolution. Under this physiological framework, the excitement phase is characterized by rapid vasocongestion (e.g., vaginal lubrication, penile erection, labial engorgement) initiated by somatosensory or psychogenic stimulation. The HISE explicitly targets this first phase, offering an operationalized metric of how an individual negotiates the physiological and subjective entry into the excitement phase.
Kaplan's Triphasic Model and Basson's Circular Model
Helen Singer Kaplan (1979) refined Masters and Johnson's model by introducing sexual desire as an independent precursor to excitement, creating the Triphasic Model (Desire, Arousal, Orgasm). This theoretical separation directly influenced Hurlbert's psychometric philosophy: by developing independent indices for sexual desire (HISD) and sexual excitability (HISE), Hurlbert and colleagues established that an individual could possess high sexual desire yet exhibit low physiological or subjective excitability, or conversely, possess low spontaneous desire while maintaining robust capacity for arousal once erotic stimulation commenced.
Furthermore, the structure of the HISE aligns with Rosemary Basson's circular model of female sexual response. Basson postulated that women often begin sexual encounters from a state of sexual neutrality; exposure to nonsexual intimacy or foreplay triggers subjective arousal, which secondarily ignites conscious desire. Several HISE items directly assess this dynamic—for instance, evaluating whether an individual can become aroused even when not initially "in the mood," emphasizing responsive rather than purely spontaneous excitation.
The Dual Control Model of Sexual Response
Although conceptualized shortly before the formalization of the Dual Control Model of Sexual Response by John Bancroft and Erick Janssen at the Kinsey Institute (Janssen & Bancroft, 2007), the HISE serves as an empirical precursor to this paradigm. The Dual Control Model posits that sexual response is governed by two independent, neurobiologically grounded systems: Sexual Excitation (SE, neurochemical activation involving dopamine, oxytocin, and melanocortins) and Sexual Inhibition (SI, central nervous system braking mediated by serotonin, endocannabinoids, and noradrenaline). The HISE primarily assesses the manifest behavioral and subjective output of the Sexual Excitation system, tracking how easily positive erotic cues overcome baseline neurobehavioral thresholds.
Validity
The construct, convergent, discriminant, and criterion-related validity of the HISE have been substantiated through multiple empirical investigations involving non-clinical married couples, clinical cohorts presenting with sexual dysfunctions, and diverse community samples.
Construct and Factorial Validity
In the seminal validation study conducted by Hurlbert, Apt, and Rabehl (1993), the HISE was administered to a normative sample of women in nondistressed marriages alongside measures of sexual satisfaction, marital quality, and sexual behavior. The HISE exhibited high item-total correlation coefficients across all 25 items (ranging from .42 to .78), establishing that every statement contributed meaningfully to the overarching construct of sexual excitability without redundant overlap. Confirmatory studies verify that the scale cleanly captures variance distinct from affective disposition and social desirability biases.
Convergent Validity
Convergent validity is documented through robust, statistically significant correlations with validated instruments assessing related psychosexual dimensions:
- Sexual Assertiveness: Strong positive correlations ($r = .55$ to $.68, p < .001$) are consistently observed between the HISE and the Hurlbert Index of Sexual Assertiveness (HISA). Individuals who can initiate sex, communicate their erotic preferences, and refuse unwanted sexual activity report significantly higher sexual excitability.
- Sexual Desire: The HISE demonstrates moderate-to-high correlations with the Hurlbert Index of Sexual Desire ($r = .50$ to $.62$), reflecting the natural theoretical relationship between sexual interest and physical/psychological arousability while remaining sufficiently distinct ($r^2 < .40$) to prove construct divergence.
- Orgasmic Functioning: Higher HISE scores correlate with greater orgasmic consistency ($r = .48$ to $.60$), corroborating physiological evidence that robust, sustained arousal is a necessary prerequisite for reaching the orgasmic threshold.
- Female Sexual Function Index (FSFI): In subsequent validation cohorts, the HISE demonstrated strong convergent alignment with the Arousal and Lubrication domains of the FSFI ($r = .64$ to $.72, p < .001$).
Discriminant Validity
The HISE demonstrates distinct discriminant validity against non-sexual psychological and relational variables:
- Marital Satisfaction: When evaluated against general dyadic adjustment scales (such as the Dyadic Adjustment Scale, DAS), the HISE correlates moderately ($r = .25$ to $.35$), confirming that while marital harmony contributes positively to sexual comfort, sexual excitability represents an individual psychosexual trait that does not merely mirror overall relationship happiness.
- Affective Distress: Correlations with generalized anxiety and depressive inventories (e.g., Beck Depression Inventory) remain low to modest (typically $r = -.18$ to $-.28$), demonstrating that low excitability is not merely an artifact of negative affectivity, but a distinct functional and subjective presentation.
Criterion and Clinical Validity
The scale reliably differentiates between clinical populations diagnosed with Female Sexual Arousal Disorder or Hypoactive Sexual Desire Disorder and non-dysfunctional controls ($t$-tests showing differences significant at $p < .001$). Furthermore, pre- and post-intervention evaluations of couples undergoing sensate focus therapy reveal marked, statistically significant increases in HISE composite scores ($d > 0.80$), confirming the scale's sensitivity to therapeutic change.
Reliability
The Hurlbert Index of Sexual Excitability displays outstanding psychometric reliability across diverse testing conditions, demographics, and study methodologies.
Internal Consistency
In the original validation study by Hurlbert et al. (1993), the instrument yielded a high internal consistency reliability coefficient, with an overall Cronbach's alpha ($lpha$) of .91. Subsequent investigations utilizing the HISE in independent cohorts have consistently replicated these findings:
- Normative female marital samples: $lpha = .89 – .92$
- Clinical samples presenting for sex therapy: $lpha = .91 – .94$
- Mixed-gender community cohorts: $lpha = .90 – .93$
Item-total correlations across studies consistently surpass the psychometric threshold of .30, with most items falling between .45 and .74. Furthermore, split-half reliability coefficients using the Spearman-Brown prophecy formula have consistently yielded values exceeding .88.
Test-Retest Stability
The temporal stability of the HISE has been demonstrated over various evaluation windows. In a four-week test-retest reliability trial conducted with non-clinical participants who experienced no therapeutic or life status interventions, the Pearson correlation coefficient was $r = .86$ ($p < .001$). A shorter two-week retest interval yielded an even stronger coefficient of $r = .91$. These findings confirm that while sexual excitability fluctuates naturally based on immediate context and state arousal, baseline excitability represents a stable trait-like disposition over time in the absence of targeted psychological or medical interventions.
Standard Error of Measurement
The Standard Error of Measurement (SEM) for the HISE is approximately 3.2 to 3.8 points across the 0–100 point continuum. This narrow band affords clinicians high confidence when interpreting individual patient trajectories, ensuring that changes exceeding 8 points on the composite scale reflect genuine clinical transformation rather than random psychometric fluctuation.
Factor Analysis
The structural dimensionality of the HISE has been examined using both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA).
Exploratory Factor Structure
Principal Axis Factoring and Principal Components Analysis with Varimax and Promax rotations consistently reveal a dominant first general factor accounting for approximately 42% to 48% of the total variance. This strong primary factor demonstrates that the scale functions effectively as a unidimensional instrument for calculating an overall index of sexual excitability.
When multi-factor solutions are extracted based on the Kaiser criterion (eigenvalues > 1.0) and scree plot inspections, four coherent, clinically meaningful sub-dimensions emerge:
- Factor 1: Subjective Arousal Readiness & Lubrication/Tumescence (Eigenvalue ~ 10.5): Accounting for the majority of the common variance, this factor encompasses items measuring direct ease or difficulty in experiencing excitement (e.g., Items 4, 6, 7, 18, 22, 23). Items load between .58 and .79.
- Factor 2: Partner-Directed Erotic Responsiveness (Eigenvalue ~ 2.4): Captures sexual arousal triggered specifically by intimate partner interactions, including foreplay, oral sex, kissing, and intercourse (e.g., Items 1, 2, 9, 12, 15, 17, 21, 24). Loadings range from .51 to .74.
- Factor 3: Maintenance & Arousal Stability (Eigenvalue ~ 1.8): Encompasses items measuring the premature decay of arousal or difficulty sustaining excitement throughout sexual activity (e.g., Items 5, 14, 20). Factor loadings range from .62 to .81.
- Factor 4: Autonomic & Cognitive Eroticism (Eigenvalue ~ 1.3): Groups items reflecting non-coital, solitary, or fantasy-based arousal, including masturbation and erotic thoughts (e.g., Items 10, 11, 13). Loadings fall between .46 and .69.
Confirmatory Factor Analysis and Model Fit
In structural equation modeling evaluating whether the HISE is best represented as a strict unidimensional model versus a hierarchical, higher-order model (where the four sub-factors load onto a single higher-order Sexual Excitability construct), the higher-order hierarchical model displays superior fit indices across empirical studies:
- Comparative Fit Index (CFI): .93 to .95
- Tucker-Lewis Index (TLI): .92 to .94
- Root Mean Square Error of Approximation (RMSEA): .052 (90% CI [.044, .060])
- Standardized Root Mean Square Residual (SRMR): .048
These fit indices indicate that while clinical researchers can examine specific item clusters to diagnose targeted issues (such as maintenance decay versus initiation latency), the composite sum remains the most robust, psychometrically stable metric.
Instrument / Measurement Tool
- Test Type: Standardized self-report psychometric rating scale
- Format: Paper-and-pencil or secure digital/web-based questionnaire
- Number of Items: 25 items
- Administration Time: Approximately 5 to 10 minutes
- Target Population: Adults (18+ years of age) engaging in partnered or solitary sexual activity; validated extensively in female cohorts and widely used in mixed-gender clinical and research contexts
- Response Format: 5-point Likert-type scale with the following anchors:
- All of the time = 0 points
- Most of the time = 1 point
- Some of the time = 2 points
- Rarely = 3 points
- Never = 4 points
- Item Polarity and Reverse Scoring:
- Reverse-Scored Items (13 items): Items 1, 2, 3, 9, 10, 11, 12, 13, 15, 17, 19, 21, 24, and 25. These items describe positive, high-excitability states. Because the raw scoring scale assigns 0 to "all of the time" and 4 to "never," these items are inverted prior to final scoring: $$\text{Scoring Key for (R) items: } 0 \rightarrow 4,; 1 \rightarrow 3,; 2 \rightarrow 2,; 3 \rightarrow 1,; 4 \rightarrow 0$$
- Standard-Scored Items (12 items): Items 4, 5, 6, 7, 8, 14, 16, 18, 20, 22, and 23. These items describe arousal difficulties, latency, loss of excitement, or boredom. They retain their natural raw response values ($0 = \text{all of the time}, dots, 4 = \text{never}$). Thus, answering "never" to a difficulty item awards 4 points, indicating high excitability.
- Scoring and Interpretation:
- Total Score Range: 0 to 100 points.
- Calculation: Sum the points across all 25 items (using inverted values for the 13 reverse-scored items and raw values for the 12 standard items).
- Directionality: Higher cumulative scores reflect greater levels of sexual excitability, lower arousal latency, and superior arousal maintenance.
- Score Stratification:
- 0 – 49: Low sexual excitability (frequently indicates clinical arousal difficulties, FSAD, severe performance inhibition, or psychosexual distress)
- 50 – 74: Moderate / Average sexual excitability (typical of community cohorts with situational fluctuations in arousal)
- 75 – 100: High sexual excitability (characterizes individuals with high erotic receptivity, minimal arousal latency, and stable maintenance)
Permissions & Fee and Test Year
The Hurlbert Index of Sexual Excitability was formally published in 1993 in the Journal of Sex & Marital Therapy. The scale was developed by David F. Hurlbert, Carol Apt, and S. Michael Rabehl.
- Copyright & Commercial Status: The instrument is held under standard academic copyright via the original publisher (Taylor & Francis / Routledge). However, consistent with Dr. Hurlbert's psychometric instrumentation (such as the Hurlbert Index of Sexual Assertiveness), the scale is generally accessible without royalty fees for academic, clinical non-profit, and empirical research purposes, provided proper scholarly citation is maintained.
- Permissions: Commercial use, inclusion in fee-for-service digital health platforms, or reproduction within commercial publications requires written permission from the copyright holders or current rights administrators. Researchers planning empirical trials may contact the original publishing body or reference the primary 1993 publication.
References
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