Democratic women wear white as President Trump delivers his first address before a joint session of Congress on Feb. 28. (Photo by Melina Mara /The Washington Post)

Congress has a gender imbalance. Of 435 members of the House of Representatives, just 83, or 19.1 percent, are women, putting the United States at 101st in gender balance among the world’s national legislatures.

But what about House staff? Is there a gender disparity there too?

Well, it’s complicated.

At first glance, House staff gender statistics look fairly equitable. Women make up roughly half of lawmakers’ personal office aides. Such staff equity, however, masks several gendered divisions among House members’ more than 6,000 personal aides.

Women toil in districts, men dominate the Hill

Congressional staff are divided between members’ Capitol Hill and home district offices. We used the Spring 2016 Leadership Directories to identify the universe of House staff and their assigned responsibilities. To determine staff gender, we use Baby Name Guide.com. We excluded any staff with names with inclusive gender, such as Alex or Taylor.

Several trends emerge from the data.

First, as you can see in the figure below, women dominate jobs with administrative and constituent-service responsibilities. Indeed, more than half of female congressional staff work outside Washington in members’ district offices. Of the eight most common House district position titles, six skew heavily female, including district schedulers (85 percent); caseworkers (77 percent); and constituent service representatives (68 percent).

Second, men represent the majority of only two district-based jobs: district director (53 percent) and field representative (57 percent). Both positions have managerial responsibilities and require representing the member to constituents, which few of the majority-female positions entail.

Third, on Capitol Hill, women comprise 45 percent of House staffers. Of the 12 most common House position titles, women represent a majority of just four of them. As in the districts, the only Hill job titles that are majority female are largely administrative, including scheduler (83 percent) and office manager (95 percent). (Administrative, to be clear, does not mean unimportant.)

Fourth, the most striking disparities are found in office leadership positions. Only about a third of House chiefs of staff or legislative directors are female, while 42 percent of deputy chiefs of staff are female. The picture is similar among policy staff. Women are a minority of legislative assistants (43 percent); legislative correspondents (40 percent); and legislative counsels (44 percent). Communications-related positions come closer to parity, with women representing 48 percent of communications directors and 46 percent of press secretaries.

There are gender differences within job portfolios

There also are notable differences by gender in the responsibilities granted to staffers who hold the same job titles. We can see this by examining which staffers are explicitly responsible for a policy portfolio as part of their responsibilities. Most often, that responsibility goes to legislative assistants, but legislative correspondents, legislative directors and even chiefs of staff can be assigned specific policy areas, as well.

The figure below shows the 28 policy topics that at least one-third of House offices assign to a policy staffer. Of these, just five are mostly handled by women. As you can see, only the “women’s issues” policy area leans heavily female, with women making up 73 percent of staffers assigned that topic. The other four issues — animals, education, health care and Medicare/Medicaid — are each less than 55 percent female, giving women only slight majorities.

In contrast, men dominate national defense and homeland security portfolios. Moreover, men have a greater than 20 percentage-point majority in 21 of the 28 issue areas, including issues considered prestigious, such as appropriations (39 percent female) and budget (33 percent), and policy-wonk issue areas such as the environment (33 percent) and financial services (32 percent).

How does this break down by party?

As with the overall composition of House aides, on the surface, the two major parties’ staffers appear balanced by gender. Among Republican House staffers, 49 percent are female, while 54 percent of Democratic staffers are women. But a closer look reveals deeper discrepancies between House members of each of the parties.

Some of the largest partisan gender disparities are seen in leadership positions. Republicans are 15 percentage points less likely to employ women as a chief of staff or legislative director than are Democrats, and are 26 percentage points less likely to have female legislative counsels. A notable exception is that Republican members are 15 percentage points more likely than Democrats to have female deputy chiefs of staff.

When looking at policy portfolios, Democrats are 10 percentage points more likely to assign female staffers to any given issue area than are Republicans. Of the 28 policy areas, Democrats have a higher proportion of female legislative aides on 22. Republicans assign a higher proportion of female legislative staffers than Democrats for only six of the 28.

Why does this matter?

Scholars and observers of Congress have long argued that female representation affects government processes and legislative outcomes, both substantively and symbolically.

Substantively, women lawmakers have been shown to devote more attention and political capital than their male counterparts to such issues as child care, rehabilitation programs and fiscal crises. Additionally, studies have found that women bring a more collaborative and congenial leadership style to governance than do men.

Staffers are likely to have similar effects. After all, legislative aides conduct much of the work in Congress and can help to shape their bosses’ positions and votes. The underrepresentation of women among congressional staff — particularly in leadership and key policy positions — means their backgrounds, perspectives and voices are underrepresented in the legislative process.

Casey Burgat is a governance fellow at the R Street Institute.