Background/Objective: Masturbation has historically been a sexual behaviour associated with negative connotations, as a consequence of traditional orthodox positions, despite its positive impact on health. The instruments developed to measure the attitude towards masturbation are scarce, and none of them have been validated in the Spanish adult population. This study aims to propose a short version of the Negative Attitudes Toward Masturbation Inventory (NATMI) and examine their psychometric properties (reliability and evidence of validity) in the Spanish adult population. Method: A total of 4,116 heterosexual adults aged 18-83 years (M = 40.58; SD = 12.24; 54.64% women) participated in the study. In addition to the NATMI, they answered other scales to assess sexual attitudes, sexual desire, propensity to become sexually excited/inhibited and sexual functioning. Results: Analysis of the construct validity of the NATMI resulted in a reduced version of ten items grouped into a single factor explaining 66% of the variance (ordinal alpha = .95). The evidence of validity is clear, as subjects with negative and positive attitude towards masturbation differed in religiousness, frequency of masturbation, erotophilia, positive attitude towards sexual fantasies, sexual inhibition and sexual functioning. Conclusions: The Spanish short version of NATMI provides reliable and valid measures in the Spanish adult population.

背景/目的：自慰在历史上一直是一种与负面含义相关的性行为，这是传统正统立场的结果，尽管它对健康有积极影响。用于衡量对自慰态度的工具很少，而且没有一个在西班牙成年人中得到验证。本研究旨在提出简短版本的自慰消极态度量表 (NATMI)，并检查其在西班牙成年人群中的心理测量特性（可靠性和有效性证据）。方法：共有 4,116 名年龄在 18-83 岁的异性恋成年人（M = 40.58；SD = 12.24；54.64% 女性）参与了这项研究。除了 NATMI 之外，他们还回答了其他量表来评估性态度、性欲、性兴奋/性抑制倾向以及性功能。结果：对 NATMI 结构效度的分析得出了 10 个项目的简化版本，这些项目被分组为单个因素，解释了 66% 的方差（序数 alpha = .95）。有效性的证据是明确的，因为对手淫持消极和积极态度的受试者在宗教信仰、手淫频率、性欲、对性幻想的积极态度、性抑制和性功能方面存在差异。结论：西班牙语简短版 NATMI 为西班牙成年人口提供了可靠且有效的措施。