There are four forms of the SDTLA. Form 1.99 is made up of 153 items and assesses three developmental tasks and two scales. Form 2.99 is made up of 57 items and measures the Establishing and Clarifying Purpose Task (Career Planning, Lifestyle Planning, Cultural Participation, and Educational Involvement Subtask), plus the Response Bias Scale. Form 3.99 is made up of 57 items and measures the Developing Autonomy Task (Emotional Autonomy, Instrumental Autonomy, Interdependence, and Academic Autonomy Subtasks), plus the Response Bias Scale. Form 4.99 is made up of 47 items and measures the Developing Mature Interpersonal Relationships Task (Tolerance and Peer Relationships) and Salubrious Lifestyle Scale, plus the Response Bias Scale.
Form 1.99 requires 25 to 35 minutes to complete. Forms 2.99 and 3.99 require 15 to 20 minutes to complete, and Form 4.99 requires 10 to 15 minutes to complete.
Reading Level. The SDTLA is an untimed instrument, but the time necessary to complete may be affected by students' reading levels. The overall reading level of the SDTLA is between grade 11.2 and 11.5. If the SDTLA is used with students below grade 12 reading level, the instrument administrator should plan additional time and make provisions to explain the meanings of some words privately.
It may be advisable to read the instructions related to providing the demographic information to students before they begin. This information may be collected in a variety of places on an optical scan answer sheet, depending on the publisher and the given format of the answer sheet. It should be emphasized that obtaining the demographic information, especially sex and class standing, is essential to scoring the instrument.