Measurement invariance in gender and age of the Herth Hope Index to the general spanish population across the lifespan.

The Herth Hope Index (HHI) is used to measure hope. Assessing the psychometric properties of HHI in Spanish population, exploring its structural validity, the different functionalities of the items and the invariability of this measure according to the gender and age of the population. Confirmatory factor analysis was conducted to explore the scale's dimensionality and test for strong measurement invariance across sex and age in a cross-sectional, multicenter, prospective study. A new scale was obtained with the structure of one factor with 9 items. Goodness-of-fit indices were excellent. The internal consistency of the one dimension proved high values. The configural invariance on gender shows that both men and women understand the new HHI items, also, this research also shows that there is no scalar invariance across age groups, revealing good levels of adjustment of the item. The Spanish version of the HHI proved to be a valid, reliable instrument to assess the hope in Spanish population.