The Schedule for Affective Disorders and Schizophrenia (SADS) is a collection of psychiatric diagnostic criteria and symptom rating scales originally published in 1978.
It is organised as a semi-structured diagnostic interview. The structured aspect is that every interview asks screening questions about the same set of disorders regardless of the presenting problem; and positive screens get explored with a consistent set of symptoms. These features increase the sensitivity of the interview and the inter-rater reliability (or reproducibility) of the resulting diagnoses. The SADS also allows more flexibility than fully structured interviews: Interviewers can use their own words and rephrase questions, and some clinical judgment is used to score responses.
There are three versions of the schedule:
The regular SADS;
The lifetime version (SADS-L); and
A version for measuring the change in symptomology (SADS-C).
Although largely replaced by more structured interviews that follow diagnostic criteria such as DSM-IV and DSM-5, and specific mood rating scales, versions of the SADS are still used in some research papers today.
Relationship with the Research Diagnostic Criteria
The SADS was developed by the same group of researchers as the Research Diagnostic Criteria (RDC). While the RDC is a list of diagnostic criteria for psychiatric disorders, the SADS interview allows diagnoses based on RDC criteria to be made, and also rates subject’s symptoms and level of functioning.
The K-SADS (or Kiddie-SADS) is a version of the SADS adapted for school-aged children of 6–18 years. There are various different versions of the K-SADS, each varying slightly in terms of disorders and specific symptoms covered, as well as the scale range used. All of the variations are still semi-structured interviews, giving the interviewer more flexibility about how to phrase and probe items, while still covering a consistent set of disorders.
The K-SADS-E (Epidemiological version) was developed for epidemiological research. It focused on current issues and episodes only. Most of the items used a four point rating scale.
The K-SADS-PL (Present and Lifetime version) is administered by interviewing the parent(s), the child, and integrating them into a summary rating that includes parent report, child report, and clinical observations during the interview. The interview covers both present issues (i.e., the reason the family is seeking an evaluation) as well as past episodes of the disorders. Most items use a three point rating scale for severity (not present, subthreshold, and threshold – which combines both moderate and severe presentations). It has been used with preschool as well as school-aged children. A 2009 working draft removed all reference to the DSM-III-R criteria (which were replaced with the publication of the DSM-IV in 1994) and made some other modifications. A DSM-5 version is being prepared and validated.
The WASH-U K-SADS (Washington University version) added items to the depression and mania modules and used a six point severity rating for severity.
The Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS) is a semi-structured interview aimed at early diagnosis of affective disorders such as depression, bipolar disorder, and anxiety disorder. There are currently four different versions of the test that are structured to include interviews with both the child and the parents or guardians.
The K-SADS serves to diagnose childhood mental disorders in school-aged children 6-18. The different adaptations of the K-SADS were written by different researchers and are used to screen for many affective and psychotic disorders. Versions of the K-SADS are semi-structured interviews administered by health care providers or highly trained clinical researchers, which gives more flexibility to the interviewer about how to phrase and probe items, while still covering a consistent set of disorders. Due to its semi-structured interview format, time to complete the administration varies based on the youth/adult being interviewed. Most versions of the K-SADS also include “probes”, if these are endorsed, another diagnostic category will be reviewed. If the probe is not endorsed, additional symptoms for that particular disorder will not be queried.
The K-SADS has been found to be reliable and valid in multiple research and treatment settings.
The Schedule for Affective Disorders and Schizophrenia for School Aged Children, or K-SADS, was originally created as an adapted version of the Schedule for Affective Disorders and Schizophrenia, a measure for adults. The K-SADS was written by Chambers, Puig-Antich, et al. in the late 1970s. The K-SADS was developed to promote earlier diagnosis of affective disorders and schizophrenia in children in a way that incorporates reports by both the child and parent and a “summary score” by the interviewer based on observations and teacher ratings.
The first version of the K-SADS differed from other tests on children because it relied on answers to interview questions rather than observances during games and interactions. The 1990s led to the creation of different versions of the K-SADS for different purposes, such as ascertaining lifetime diagnoses (K-SADS-E) or focusing on current episodes (K-SADS-P).
KSADS-Present Version (KSADS-P)
The KSADS-P was the first version of the K-SADS, developed by Chambers and Puig-Antich in 1978 as a version of the Schedule for Affective Disorders and Schizophrenia adapted for use with children and adolescents 6-19 years old. This version rephrased the SADS to make the wording of the questionnaire pertain to a younger age group. For example, mania symptoms in children might be manifest differently than in adulthood (e.g. children might have not have the same opportunity to spend money impulsively, nor would they likely have access to credit cards or checking accounts; instead, they might give away all their favourite toys or empty their parent’s wallet to gain spending money). The KSADS-P is a structured interview given by trained clinicians or clinical researchers who interview both the child and the parent. This original version assesses symptoms that have occurred in the most current episode (within the week preceding the interview), as well as symptoms that have occurred within the last 12 months. The KSADS-P has many limitations: it does not assess lifetime symptoms and history, does not include many psychiatric diagnoses of interest in childhood (such as autistic spectrum disorders), and does not include diagnosis specific impairment ratings.
KSADS-Present and Lifetime Version (KSADS-PL)
The K-SADS-PL is used to screen for affective and psychotic disorders as well as other disorders, including, but not limited to Major Depressive Disorder, Mania, Bipolar Disorders, Schizophrenia, Schizoaffective Disorder, Generalized Anxiety, Obsessive Compulsive Disorder, Attention Deficit Hyperactivity Disorder, Conduct Disorder, Anorexia Nervosa, Bulimia, and Post-Traumatic Stress Disorder. This semi-structured interview takes 45-75 minutes to administer. It was written by Joan Kaufman, Boris Birmaher, David Brent, Uma Rao, and Neal Ryan. The majority of items in the K-SADS-PL are scored using a 0-3 point rating scale. Scores of 0 indicate no information is available; scores of 1 suggest the symptom is not present; scores of 2 indicate sub-threshold presentation and scores of 3 indicate threshold presentation of symptoms. The KSADS-PL has six components:
Unstructured Introductory Interview – Developmental History
The first part of the interview asks about developmental history and the history of the presenting problem. The interviewer takes detailed notes on the record sheet. Prompts cover basic demographic information, physical and mental health history and prior treatments, current complaints, and the youth’s relations with friends, family, school, and hobbies. This section allows flexibility for the interviewer to collect more information on questions that need elaboration.
Diagnostic Screening Interview
The diagnostic screening interview reviews the most severe current and past symptoms. There are probes and scoring criteria for each symptom presented. Symptoms of disorders are grouped into modules. If the patient does not display any current or past symptoms for the screening questions, then the rest of the module’s questions do not need to be asked.
Completion Checklist Supplement
A supplemental checklist is used to screen for additional disorders.
Appropriate Diagnostic Supplements
These supplements review presence/absence of symptoms for other disorders, including anxiety disorders, behavioural disorders, and substance abuse.
Summary Lifetime Diagnosis Checklist
Based on the previous sections, this section summarises which disorders have been present from first episode to now.
Children’s Global Assessment Scale (C-GAS)
Scores the child’s level of functioning.
The KSADS-E, which is the epidemiological version of the KSADS, is a tool to interview parents about possible psychopathology in children from preschool onward. It was developed by Puig-Antich, Orvaschel, Tabrizi, and Chambers in 1980 as a structured interview. The tool examines both past and current episodes, focusing on the most severe past episode and the most current episode. However, this tool does not rate symptom severity; it should only be used to assess presence or absence of symptomatology. This version of the K-SADS introduced screening questions, which, if negative, allowed skipping the remaining diagnostic probes. Furthermore, the K-SADS-E also includes “skip out” criteria when assessing other diagnostic disorders (ADHD, PTSD, etc.), allowing those that screen positive to immediately be interviewed for all of the symptoms regarding that diagnosis, and those that screened negative could “skip out” of being interviewed on the remaining symptoms.
The WASH-U version of the K-SADS was written by Barbara Geller and colleagues in 1996. It is a modified version of the 1986 K-SADS. This version is like many other versions of the K-SADS in that it is semi-structured, administered by clinicians to both parent and child separately, and assesses present episodes. However, this version specifically expands the mania section in order to be more applicable to pre-pubertal mania. In particular, it queries presence/absence of rapid cycling. It also includes a section on multiple other DSM-IV diagnoses, and examines both present and lifetime symptoms as well as symptom onset and offset items. These modifications made this specific version particularly useful for phenomenology studies.
KSADS Mania Rating Scale (KMRS) and Depression Rating Scale (KDRS) It also is possible to use the items in the mania and depression modules of some versions of the KSADS to get an interview-based rating of the severity of mood problems. The KMRS and KDRS use a 1 to 6 rating format (the same as in the WASH-U, -P, and PL-Plus versions). Adding up the items provides a measure of the total symptom burden. The KMRS assess 21 symptoms related to mania, hypomania, and rapid cycling. Each item is rated on a 0-6 rating scale. Scores of 0 suggest no information is available (missing data); scores of 1 suggest the symptom is not present at all; scores of 2 suggest the symptom is slightly present; scores of 3 suggest the symptom is mildly severe; scores of 4 suggest the symptom is moderately severe; scores of 5 suggest the symptom is severe; and scores of 6 suggest the symptom is extremely severe. Items with scores of 4 or higher are clinically significant/problematic. Trained clinicians or clinical researchers administer the assessment to both the child and the parent, which each provide their own separate score for each item (P and C), and the total score encompasses the sum of all of the items (S).
The KMRS is an alternative to the Young Mania Rating Scale designed by Young et al. (frequently referred to as the YMRS). The YMRS is more well-known and widely used, but because it was written in 1978, it does not include all of the symptoms of mania from ICD-9 or ICD-10 (nor DSM-IV or DSM-5), as it predated them all. The YMRS was also designed for completion by nurses at the end of their eight-hour shift on an inpatient unit, observing adult patients. The KMRS has several advantages in comparison: It covers all the symptoms used in current versions of ICD and DSM, it was designed for use with children and teenagers, and it was written and validated as an interview. Studies have found excellent internal consistency and inter-rater reliability, as well as exceptionally high correlation with the YMRS. Similarly, the KDRS would be analogous to the Child Depression Rating Scale-Revised. The CDRS-R was also designed to be done as an interview, but the item content predates the current ICD and DSM and omits some important symptoms. The KDRS also shows strong reliability (internal consistency and inter-rater) and exceptionally high correlations with the KDRS.
The K-SADS is used to measure previous and current symptoms of affective, anxiety, psychotic, and disruptive behaviour disorders. The K-SADS has become one of the most widely used diagnostic interviews in research, particular for projects focused on mood disorders.
The K-SADS-PL has been written and translated into 16 different languages, including Korean, Hebrew, Turkish, Icelandic, and Persian. The K-SADS-PL is also available in several Indian dialects including Kannada, Marathi, Tamil and Telugu.
One limitation of the K-SADS is that it requires extensive training to give properly, including observation techniques, score calibration, and re-checks to test inter-rater reliability.