Sex differences in application, success, and funding rates for NIH extramural programs

Abstract

Purpose: The authors provide an analysis of sex differences in National Institutes of Health (NIH) award programs to inform potential initiatives for promoting diversity in the research workforce.

Method: In 2010, the authors retrieved data for NIH extramural grants in the electronic Research Administration Information for Management, Planning, and Coordination II database and used statistical analysis to determine any sex differences in securing NIH funding, as well as subsequent success of researchers who had already received independent NIH support.

Results: Success and funding rates for men and women were not significantly different in most award programs. Furthermore, in programs where participation was lower for women than men, the disparity was primarily related to a lower percentage of women applicants compared with men, rather than decreased success rates or funding rates. However, for subsequent grants, both application and funding rates were generally higher for men than for women.

Conclusions: Cross-sectional analysis showed that women and men were generally equally successful at all career stages, but longitudinal analysis showed that men with previous experience as NIH grantees had higher application and funding rates than women at similar career points. On average, although women received larger R01 awards than men, men had more R01 awards than women at all points in their careers. Therefore, while greater participation of women in NIH programs is under way, further action will be required to eradicate remaining sex differences.

Figure 1

Multiple R01 awards in 2008 and the participation of women, by age. Participation of women, by number of concurrent R01 awards. The percentage of female investigators is shown for the indicated number of concurrent R01 awards in 2008. The total awards in each cohort are indicated, as well as the average ages of females and males in each cohort.

Figure 2

Number of concurrent R01 awards in 2008, by age cohort. The average number of concurrent R01 awards in 2008 is shown in two-year increments for ages 30 – 66.

Chart 1

Person-level and Application-level Data for Selected 2008 Competing National Institutes of Health Applications and Awards, by Activity Code (Award Mechanism) and Sex, in Order of Increasing Average Age within each Career Stage (Early – Independent – Mid – Senior) * Binomial test was used to determine if the percentage of women or men in the applicant or awardee pool was different from 50%. † Distribution comparisons between males and females were performed with the 2-sample Kolmogorov-Smirnov test. ‡ Values shown are averages. § Pearson’s chi-square test was used to assess sex differences. ¶ Applications with incomplete values for direct costs were excluded from cost calculations. ** Only full-time trainees appointed to FY2008 competing awards were included; trainees are not NIH awardees because the trainees are selected by the institution. †† P<.05.

Chart 1

Person-level and Application-level Data for Selected 2008 Competing National Institutes of Health Applications and Awards, by Activity Code (Award Mechanism) and Sex, in Order of Increasing Average Age within each Career Stage (Early – Independent – Mid – Senior) * Binomial test was used to determine if the percentage of women or men in the applicant or awardee pool was different from 50%. † Distribution comparisons between males and females were performed with the 2-sample Kolmogorov-Smirnov test. ‡ Values shown are averages. § Pearson’s chi-square test was used to assess sex differences. ¶ Applications with incomplete values for direct costs were excluded from cost calculations. ** Only full-time trainees appointed to FY2008 competing awards were included; trainees are not NIH awardees because the trainees are selected by the institution. †† P<.05.