Glossary Please select an letter from the A-Z list or search # A B C D E F G H I J K L M N O P Q R S T U V W X Y Z q4h Abbreviation of a Latin term meaning every four hours. QALY Quality adjusted life year. Used in studies dealing with cost-effectiveness and life expectancy, this gives a higher value to a year lived with good health than a year lived with poor health, pain or disability. qd Abbreviation of a Latin term meaning once every day. qw Abbreviation of a Latin term meaning every week.