This website uses cookies to store information on your computer. Some of these cookies are used for visitor analysis, others are essential to making our site function properly and improve the user experience. By using this site, you consent to the placement of these cookies. Click Accept to consent and dismiss this message or Deny to leave this website. Read our Privacy Statement for more.
Join Mailing List   |   Jobs   |   Print Page   |   Contact Us   |   Sign In   |   Join
Share |

Towards precise and rapid diagnosis of heparin-induced thrombocytopenia: a prospective, multicentre cohort study

 Background • Data Entry • Support

Study overview:

Diagnostic tests for heparin-induced thrombocytopenia (HIT) are associated with important drawbacks and some authors consider current diagnostic approaches to be inadequate in clinical practice. The aim of the present study is to study the accuracy of current diagnostic instruments and to assess factors that influence diagnostic accuracy. In addition, we will develop a clinical prediction rule for the diagnosis of HIT. In a first phase of the study, we will include 750 patients with suspected HIT. Our evaluation study will seek to establish that the diagnosis of HIT can be accurately predicted in individual patients at the bedside. Participation in this study not only helps improving care in patients with suspected HIT, but associates institutions with current concepts of diagnostic procedures. We invite all colleagues caring for patients with suspected HIT to evaluate feasibility of implementation at their institution and become a member of our study group.

Study Design:

In a prospective, multicenter cohort study, we will include 750 patients with suspected HIT. We will collect a number of clinical characteristics and laboratory data that are routinely obtained in clinical practice. Additionally immunassays and a reference standard test (HIPA) will be conducted in the central laboratory using residual serum samples.


  • Study Administration: 

TORADI-HIT Study, Administration
Department of Haematology
Inselspital University Hospital
3010 Bern
Phone +41 31 632 2405

  • Principle investigator:

Michael Nagler, MD, PhD, MSc
Department of Haematology
Inselspital University Hospital
3010 Bern, Switzerland


Interested Paticipants:

Submit your feasibility of implementing the study at your centre

                   TORADI- HIT Pocket card

Important Information

Background and rationale:

Heparin-induced thrombocytopenia (HIT) is a life-threatening complication of heparin treatment, which affects a significant number of patients. If missed and untreated, HIT often leads to very serious consequences. Available diagnostic tests, however, are associated with important drawbacks. In clinical practice, we not only miss patients suffering from HIT but also unnecessarily treat many patients without HIT with costly and risky alternative anticoagulants. Hence, many authors consider current diagnostic approaches to be inadequate in clinical practice.

Aim and Objectives:

The aim of the present study is to study the accuracy of current diagnostic instruments and to assess factors that influence diagnostic accuracy. In addition, we aim to develop a clinical prediction rule for the diagnosis of HIT.

Inclusion Criteria:

Patients with suspected HIT as defined as:

  • Anti-PF4/heparin antibody test (immunoassay) requested, or 
  • Clinical assessment tool (e.g. 4Ts score) applied, or
  • Consultancy team is requested, and
  • Age at least 18 years

Inclusion procedures:

  • Inclusion criteria fulfilled?
  • General consent or individual signed consent available?
  • Allocation of study-related patient-ID by using adhesive labels provided.

Data Entry:

The study centers are asked to collect a number of clinical characteristics as well as laboratory results. It is very important that the clinical characteristics are obtained accurately. To support collection of data at your institution, you may use a printout of the questionnaire mentioned below or a copy of the form we use at the PI's institution (LINK). To motivate your team, we provide a compensation for every patient included (see below). You are kindly asked to train your team adequately regarding the collection of clinical data. Data entry into the web-based database requires between 15 and 30 minutes per patient (including follow-up form). The data will be recorded in a REDCap database, the respective link is provided below. Before inclusion of patients, you must implement the study at your center by filling the feasibility form below, and submit the protocol to your local ethical committee.

Data Requested:

Printouts of the questionnaires requested are provided below. You might use these printouts for data collection at your institution. Alternatively,  we provide a template for a paper-based data collection form, which is used at our institution (LINK). Please store the filled forms at your institution.

  1. Patient characteristics
  2. Clinical assessment
  3. Laboratory assessment
  4. Serum sample
  5. Follow-up

Administrative Support:

The administration of TORADI-HIT study will support submission of documents to your local ethics committee. We will provide you with different versions of the study protocol and other documents by request (


For every patient documented completely, we will compensate the local study procedures with 160,- CHF (corresponding to 161,- USD or 139,- EUR at the 1st of June 2018). Even though this might not cover the full costs at your institution, it may motivate to collect the clinical data accurately. Enclosed you will find the invoice for compensation. The serum samples will be shipped at a later time-point in-batch and we will cover the costs. If needed, we can also cover the costs of the local ethical committee.

Download PDF of invoice

Verification of Feasibility:

You can check the feasibility of the TORADI-HIT study at your institution by using the online form (SEE ABOVE). After submitting the form, the study administration will contact you and discuss with you how to proceed with regard to implementation.

Benefits of Participation:

Participation in this study will help to improve diagnostic instruments and consequently improve care in patients with suspected HIT. In addition, your local procedures might be improved by the standardized procedure and the data collection form provided by the study administration. Your institution will be associated with publications investigating diagnostic instruments with regard to HIT and we will present the study protocol and the results at international scientific meetings and in high-ranked international journals. We aim to present the first interims analysis at the ISTH 2019 in Melbourne.

To request the Study Protocol contact: 

Membership Management Software Powered by YourMembership  ::  Legal