FORT KNOX—The U.S. Army has initiated the biggest shift since the Vietnam War era in how it selects a key class of officers, drawing on the hiring practices of private-sector organizations and corporations such as the Boston Symphony Orchestra and Google.

The aim is to move away from techniques used for over 50 years that rely on past military jobs, physical fitness scores and the recommendations of generals to promote officers to the job of battalion commander.

The new system includes surveys by subordinates, writing tests, psychological assessments, cognitive evaluations and a series of simulated militarylike scenarios in a wooded area on base to gauge leadership and problem-solving abilities.

It stresses anonymity to eliminate any possible bias. As soon as candidates arrive, they are assigned a number and aren’t known by their names. At an interview, candidates are seated behind a black curtain, and a five-member selection panel is unable to see a candidate’s uniform, with its career-defining ribbons and patches.

In the process, officials hope to generate more information, weed out unqualified applicants and reduce or eliminate gender, racial and other biases.