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CTRI registration for a thesis: when it is needed and how to do it


What CTRI is, why a prospective interventional study must be registered before you enrol the first participant, and why submissions get queried and sent back.

  • Entry no. 10 of 18
  • Published
  • 5 min read
  • Written against the standards cited below

The guide

If your thesis is a prospective interventional study, it must be registered with the Clinical Trials Registry - India before you enrol your first participant. Not before you submit the thesis, not before you publish: before the first participant. That sentence is the whole of this guide's practical content. The rest is how to satisfy it without losing a month.

What CTRI is

CTRI[5] is India's national clinical trial register, run by the Indian Council of Medical Research and hosted by its National Institute for Research in Digital Health, the institute previously called the National Institute of Medical Statistics. The registry's own pages describe it as a free, online, public record system, and state that there is no fee for registering a trial. Registration has been mandatory for clinical trials since 15 June 2009, when the Drugs Controller General (India) required it, and the registry sits inside a wider framework: ICMR's 2017 national ethical guidelines require registration, the New Drugs and Clinical Trials Rules, 2019 govern regulatory trials, and the International Committee of Medical Journal Editors treats prospective registration in a public registry as a condition of considering a trial for publication. That last one is why registration matters even for a thesis you only intend to publish later.

A completed registration produces a public record and a CTRI number. That number goes into your thesis, into the methods of any paper that comes out of it, and into your ethics file.

Prospective means prospective

CTRI registers studies prospectively. Its own frequently asked questions state that since 1 April 2018 it registers trials only prospectively, meaning before the first patient is enrolled, and the declaration a registrant signs confirms that no participant has been enrolled before registration. The registry also states that retrospective registration, or registration based on invalid or falsified documentation, is a serious breach that will freeze the registrant's account and may be reported to the appropriate authorities.

The consequence for a thesis calendar is simple and routinely missed. Ethics approval comes first, because CTRI requires the approval letter. Registration comes second. Only then does the first patient enter the study. If you have already started recruiting there is no correct way to repair it, and you will be explaining it in your viva and again to a journal editor.

Review at the registry is not instantaneous either. The registry puts its first review at ten working days from submission, after which the study goes back to the registrant for clarifications or modifications, and the clock from there depends on how fast you answer them. Build several weeks into the plan, not several days.

Which thesis studies need it

Interventional and prospective: register. A randomised controlled trial, any comparison of two treatments or techniques that you assign, a drug or device study, a surgical or anaesthetic technique comparison, a physiotherapy or lifestyle intervention, a screening or diagnostic pathway you are introducing. All interventional.

Purely observational: registration is not mandatory, but CTRI accepts observational studies, and the registry repeats the World Health Organization's advice, when in doubt, register. A cross-sectional prevalence study, a case-control study and a record-based retrospective review are not trials, though the registry's own answer is that even a study collecting data retrospectively should be registered before data collection starts, so if you decide to register one the same deadline logic applies. A prospective cohort in which you do nothing to the patients is observational, but look again if you are adding an investigation the patient would not otherwise have had, because you may have acquired an intervention.

The registry's own declaration says that clinical studies carried out as part of a postgraduate thesis are expected to be registered, and registering an observational study is cheap insurance: some journals and some universities ask for a registration number, and you cannot obtain one retrospectively. If you are unsure which side of the line your study falls on, ask your ethics committee in writing and keep the reply. Committees answer this question constantly.

What the form asks for

Most of the form is your protocol retyped into fields. If the protocol is finished, registration is an evening's work. If it is not, the form will find every gap.

  • A public title in lay language, and a scientific title
  • The principal investigator and the site's contact details
  • Sponsor, which for a thesis is usually your institution or is self-funded, stated as such
  • Every recruitment site, with the ethics committee that approved each one
  • The health condition studied, coded as the registry asks
  • The intervention and the comparator, with dose, route and duration where applicable
  • Inclusion and exclusion criteria as written in the approved protocol
  • How the allocation sequence is generated and concealed, and the blinding
  • Primary and secondary outcomes, each with the time point at which it is measured
  • Target sample size, and the dates enrolment is expected to open and close
  • Study design and, where applicable, phase
  • The ethics committee approval letter, uploaded, plus regulatory clearance where the study requires one

Contact persons named on the form are asked to confirm by email, so use addresses that are live and monitored. A co-investigator's dead email account stalls a submission for days.

Why submissions get queried

  • Enrolment has already begun, which cannot be corrected
  • The ethics approval letter is missing, unsigned, undated, or carries a different title from the form
  • Title, objectives or sample size on the form do not match the approved protocol
  • Outcomes stated with no time point, or a primary outcome that is really three outcomes
  • A public title written in technical language
  • A multi-centre study with only one site's ethics approval uploaded
  • Source of monetary or material support left blank
  • An unconfirmed contact email address
  • An intervention described too vaguely for anyone to reproduce

Answer a query by changing the form to match the approved protocol, never by changing the protocol to match the form. If something in the study genuinely has to change, that is an amendment to your ethics committee first and a correction to the registry afterwards.

Check the current guidance, every time

CTRI's requirements, its dataset and its reading of what must be registered have changed more than once and will change again. Nothing here replaces the registry's own current instructions at ctri.nic.in, your ethics committee's direction, or, for DNB and DrNB trainees, the National Board of Examinations in Medical Sciences[2]' requirement that the ethics-approved protocol be uploaded within 180 days of joining. Check all three against your own dates before you rely on any of them.


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Document: Guide no. 10 — CTRI registration for a thesis: when it is needed and how to do it · Revision 1 · Last reviewed

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