Unable To Get Stored Procedure Output Variable Through ExecuteReader

here my code-

using (SqlDataReader sqlDataReader = ExecuteReader(CommandType.StoredProcedure, StoredProcedures.AuthenticateUser, sqlParameter))
{
isAuthenticated = Convert.ToBoolean(sqlParameter[2].Value);
if (isAuthenticated)
{
if (sqlDataReader.Read())
{
User = new UserEntity();
DbHelper.GetEntity(sqlDataReader, User);
}
}
}

I always get isAuthenticated as false because sqlParameter[2].Value is null all the time but when I execute my query with ExecuteNonQuery it gives me the value but in that case I can not fill the entity.