Orgasmic function – and, by consequence, orgasmic intensity – are among the least understood and studied parts of human sexual behavior. In general, most sexual health experts will have no issue with discussing ejaculatory function with their patients, investigating the domains of control, distress and timeliness traditionally used for definition of PE [21, 24,25,26] – however, the issue of orgasmic intensity is rarely addressed in clinical practice, and even more rarely in research. The Orgasmometer aims to fill this gap, addressing an unmet need for men and women alike [12, 13].

Our findings provide robust psychometric support for the Mandarin version of the Orgasmometer. We observed acceptable score distribution, minimal floor and ceiling effects, and strong known-groups validity, as demonstrated by ANCOVA analyses comparing men with and without PE. Even after adjusting for key covariates (age, BMI, education, and erectile function), men with PE reported significantly lower orgasm intensity than those without. This supports the construct validity of the instrument, confirming its ability to detect clinically meaningful differences in orgasmic experience between theoretically distinct groups.

The discriminant validity of the scale was further confirmed via ROC curve analysis, which demonstrated excellent accuracy in distinguishing between low and high orgasm intensity. The cutoff identified by the Youden index balanced sensitivity and specificity, further validating the utility of the instrument in both research and clinical settings. These results align with previous validations in other studies [13, 14]. Its theoretical foundation rests on the need for brief yet valid instruments to capture subjective orgasmic experiences—a domain often neglected in structured interviews or conventional scales. In this sense, the Orgasmometer-m differs from an arbitrary single-question measure, as it has undergone translation, cross-cultural adaptation, and systematic validation procedures. Interestingly, despite cultural and demographic differences between the Italian and Mandarin-speaking populations, the optimal cutoff value for distinguishing between “functional” and “non-functional” orgasmic intensity in our study closely mirrors the threshold established in the original Italian validation of the Orgasmometer [12]. This cross-cultural consistency lends further support to the scale’s discriminant validity and suggests that the subjective perception of orgasmic intensity may be comparable across different cultural contexts.

Importantly, our results reaffirm that men with PE not only report diminished ejaculatory control but also significantly lower orgasmic intensity, highlighting the broader impact of PE on sexual well-being. These findings extend earlier work by Limoncin et al. [12] and support the clinical relevance of assessing orgasm intensity in the diagnostic and therapeutic evaluation of PE.

In addition to group differences, we found that age, education level, and erectile function were significant predictors of orgasm intensity, supporting the multifactorial nature of orgasmic experience. Specifically, older age and lower educational attainment were associated with reduced orgasm intensity, while better erectile function predicted more intense orgasmic experiences. These findings are consistent with previous research showing that age-related declines in serum testosterone may impair orgasmic function [27, 28], and that sexual health literacy—which tends to be higher among individuals with more education—enhances self-awareness and communication about sexual experiences [29, 30]. For example, Banaei et al. [29] demonstrated that higher sexual health literacy improved regulation and understanding of one’s sexual response, while Warshowsky et al. [30] found structured sexuality education led to enhanced orgasm quality and confidence in sexual communication.

Our data also support emerging evidence that erectile function is intricately linked to orgasm intensity. While traditional instruments such as the IIEF assess orgasm frequency, they do not capture the intensity of orgasm, which is a distinct and clinically relevant dimension. A recent 2024 study highlighted the potential for undiagnosed orgasmic dysfunction in men with ED [31], but formal measurement tools for orgasm intensity remain underused. Although Perelman first proposed assessing orgasm intensity in ED over a decade ago [32], our study is among the first to empirically evaluate this construct using a validated instrument. Future research should assess orgasm intensity in ED populations using tools such as the Orgasmometer-m to explore this overlap in greater depth.

The present study has some strengths worth considering, such as a very selected clinical population free from possible confounding bias. Particularly relevant is the exclusion of individuals with ED. As defined by the LCEE [21], some men might experience both ED and PE at the same time: in fact, each sexual symptom might “hide” the other, resulting in clinical scenario which might be easily mistaken by the clinician as well as by the patient himself. Diabetes, another possible confounding factor, has similarly been included among exclusion criteria. In fact, diabetes can affect orgasmic function by impairing sensitive nerve transmission in the genitals [33, 34].

Despite its strengths, several limitations should be acknowledged. First, test-retest reliability and responsiveness were not assessed. Due to the nature of the sample, we did not follow up with these participants, and many participants initiated pharmacological or behavioral interventions shortly after baseline assessment, which could significantly alter orgasm intensity over time. Therefore, conducting a follow-up assessment would have compromised the validity of evaluating temporal stability. We partially addressed this issue by analyzing score distribution, variability, and group discrimination, but future studies should include longitudinal designs to assess test-retest reliability in more stable populations.

Moreover, due to the single-item nature of the Orgasmometer-m, no psychometric assessment such as Cronbach’s alpha or confirmatory factor analysis was deemed necessary. While single-item scales offer simplicity and ease of administration, they may not capture the full complexity or multidimensional nature of subjective experiences such as orgasm intensity. This limitation could potentially reduce the sensitivity of the measure to subtle variations across individuals or contexts. Furthermore, single-item instruments are more vulnerable to measurement error and may be less reliable compared to multi-item scales.

Second, the study utilized a cross-sectional design, which limits causal inferences regarding factors influencing orgasm intensity. Relatedly, while we included the frequency of sexual intercourse as a covariate, we did not assess broader dimensions of sexual behavior, such as the quality of sexual relationships or solitary sexual activity (e.g., masturbation). These factors may also influence the experience and reporting of orgasm and should be considered in future studies to better capture the full scope of sexual functioning.

Third, the sample size, although adequate for the conducted analyses, was drawn from a single center only, which may potentially affect the external validity of the results. Cultural norms and attitudes toward sexual expression and reporting may significantly influence self-reported measures of orgasm intensity. These cultural factors may differ from those in Western populations, where the original Orgasmometer was developed and validated. Therefore, caution should be exercised when extrapolating our results to broader or more diverse populations. Future validation efforts should include gender- and sexual-minority populations, as well as diverse cultural groups, to assess the instrument’s broader applicability.

Due to the cross-sectional and observational nature of our study, complete matching was not feasible. However, we attempted to control for these variables statistically by including age, BMI, and education as covariates in our ANCOVA models. Nevertheless, we acknowledge this as a limitation of our study. Residual confounding may still exist, and the demographic imbalance could impact the internal validity of our findings. Future research should aim to replicate these findings in larger, more diverse, and longitudinal cohorts to further confirm the psychometric properties of the Mandarin version of the Orgasmometer.

Another limitation of our study is the use of assessment tools, such as the XYGO, that have not been formally validated in the Mandarin language. We acknowledge that without proper validation, responses to these measures may not accurately reflect the constructs they intend to assess. Future studies should aim to use tools that have undergone standardized translation and validation processes for the target language and cultural context.

Furthermore, the study did not evaluate fertility status, which may be a relevant factor influencing sexual function. Existing research suggests that a diagnosis of infertility may negatively affect various aspects of male sexual function, including erectile confidence, ejaculatory control, and overall sexual satisfaction. It is plausible that men seeking fatherhood and facing fertility challenges may report lower orgasmic intensity. As such, future studies should include fertility-related variables to examine whether infertility is associated with differences in Orgasmometer-m scores. The present study did not collect behavioral data regarding pornography use and masturbation habits (such as frequency and technique). Previous research has shown that these factors may influence penile sensitivity and ejaculatory control, thereby affecting the orgasmic experience [35]. Future studies should include these variables to gain a more comprehensive understanding of their potential impact.