Scientists and health officials told Congress Friday the federal government needs to ramp up its supply of Covid-19 vaccine doses as they work to streamline the process for getting the shots.

Those two changes are key if federal officials want to increase the number of people who will get the shots, scientists and public health officials testified before the House Committee on Science, Space & Technology.

“Even people who are motivated and excited about the vaccine can be deterred by the smallest amount of friction in the system, whether that’s complex logistics, inconvenience or confusing instructions,” said Dr. Alison Buttenheim, scientific director for the Center for Health Incentives and Behavioral Economics.

The hearing comes as elected officials and health experts work to fight hesitancy and disinformation surrounding the Covid-19 vaccine.

“Fix the easy stuff,” Buttenheim said. “Frankly, fixing those hassle factors is often easier than changing someone’s mind.”

Dr. Philip Huang, director and health authority of the Dallas County health department, said the county tries to address “logistic and hassle factors” by offering online registration and phone banks for vaccine appointments, collaborating with community leaders to register people for vaccination, and opening drive-through vaccination sites.

Keith Reed, deputy commissioner of Oklahoma’s state health department, said the state has opened up extended timeframe to give residents more time to sign up for vaccine appointments.

“In order to vaccinate as many Oklahomans as possible, we’ve opened eligibility to new priority groups before entirely vaccinating earlier groups,” Reed said. “With this tactic, we hope to lengthen the window of opportunity.”

Initiatives that reduce logistical barriers for those eager to receive vaccinations are particularly effective as vaccine supply in the U.S. remains lower than community demand, the panelists said.

“The supply is the issue at this point,” Huang said. “We have over 650,000 people who signed up to be on our waiting list to get vaccine, and the health department’s getting 9,000 doses a week.”

Health officials emphasized that all of the Covid vaccines available in the U.S. have been effective at protecting people from severe disease, hospitalization and death. They urged people not to wait to get vaccinated in order to receive a particular brand of vaccine due to perceived efficacy.

“The best vaccine is the one you can get tomorrow,” Buttenheim said.