Principal Modeller

HEOR; Cardiff; On-site; GBP 80,000 - 100,000; Full time

Job summary

An independent market access consultancy in Cardiff is seeking a principal mathematical modeller to lead the design of innovative models crucial for market access and health outcomes. This senior role involves complex project leadership, mentoring, and direct client partnerships, particularly in oncology. Candidates should possess a deep expertise in algorithm development and statistical processes, with strong communication skills and the ability to work both independently and in a team.

Benefits

Competitive compensation

Learning culture with study bursaries

Workplace pension scheme

Private health insurance

Discounted memberships and services

Additional leave for wedding and moving

Annual leave purchase scheme

Qualifications

• Advanced academic credentials ideally in mathematics or a related scientific, engineering, or computing discipline.
• A strong grounding in statistical and stochastic processes and/or linear algebra.
• Proven ability to tackle problems proactively, whether working independently or within a focused team.

Responsibilities

• Develop, conceptualise, and build discrete numerical models of healthcare interventions.
• Lead a broad range of healthcare intervention projects and models simultaneously.
• Mentor and coach team members, fostering technical excellence and collaborative problem-solving.

Skills

Algorithm development

Statistical processes

Proactive problem-solving

Communication skills

Leadership

Curiosity and innovation

Education

Advanced academic credentials in mathematics or related field

Tools

C/C++

R

Python

VBA/Excel

Git

Job description

We are seeking a principal mathematical modeller to join our team, leading the design and development of innovative models that inform market access and health outcomes. This is a senior technical role where you will lead complex projects, mentor colleagues, and partner with clients to deliver solutions that matter, particularly in oncology and other high‑priority disease areas.

HEOR is a leading independent market access consultancy. We are driven by producing high‑quality work with scientific and technical rigour, and we take genuine pride in what we do. We work with agility and purpose, enabling us to focus on what matters most: delivering exceptional insight and supporting our clients to successfully navigate complex and ever‑changing market access challenges to optimise and articulate the value of their healthcare interventions.

What the role has to offer:

• Leadership: Collaborate closely with senior leadership to shape working practices and strategic direction for the team. Mentor and develop team members.
• Drive innovation: Lead and embed both internal and external innovation projects, developing novel solutions to complex and demanding challenges.
• Collaborate with leading experts: Work alongside a fast‑moving, forward‑thinking team dedicated to tackling complex technical challenges.

About the role

• Develop, conceptualise, and build discrete numerical models of healthcare interventions to demonstrate real‑world impact.
• Act as the technical and strategic lead on modelling projects, ensuring scientific rigour and client relevance.
• Lead a broad range of healthcare intervention projects and models simultaneously, including oncology.
• Oversee data sourcing, model protocols, and model validation, ensuring deliverables such as technical documentation meet the highest quality standards.
• Mentor and coach team members, fostering technical excellence and collaborative problem‑solving.
• Drive innovation and best practice, contributing to internal training and process‑improvement initiatives.
• Become a trusted partner to our clients, providing consultative advice on market access challenges.
• Represent the company in client meetings, proposals, and pitches, influencing strategic decisions.
• Support client development by identifying opportunities and driving the creation of technical modelling proposals.
• Contribute to research dissemination, including publications and conference presentations.

• Advanced academic credentials ideally in mathematics or a related scientific, engineering, or computing discipline, supported by deep expertise in algorithm development.
• A strong grounding in statistical and stochastic processes and/or linear algebra will set you up for success.
• A passion for algorithms and modelling, approaching complex challenges with curiosity and innovation.
• Proven ability to tackle problems proactively, whether working independently or within a focused, agile team, to drive impactful outcomes.
• A self‑starter who is confident working both independently and collaboratively, taking initiative to move projects and ideas forward.
• A growth mindset, continuously looking to improve technical methods and working practices to drive optimisation and efficiency.
• Excellent communication skills, with the ability to translate complex modelling concepts for diverse audiences.
• Experience leading projects and mentoring technical teams.
• Ability to manage multiple priorities and deliver high‑quality outputs under tight timelines.
• Familiarity with programming languages such as C/C++, R, or Python, along with an understanding of object‑oriented principles, is an asset.
• Experience developing models using best‑practice methods and version control (e.g., Git and GitHub).
• Experience with modelling within VBA/Excel is also an asset.
• Proven experience in developing economic models (e.g. budget impact, cost‑effectiveness).
• Oncology experience and cardio‑renal metabolic modelling knowledge are highly desirable.

Why join us?

• Work on strategically important projects that influence healthcare decisions globally
• Collaborate with a team passionate about scientific excellence and innovation
• Work in a fast paced and technically challenging environment – with continuous learning and development opportunities
• Opportunities for thought leadership, including publications and conference presentations

Competitive compensation and benefits package, including:

• A ‘learning’ culture focused on personal development and supported by study bursaries
• Workplace pension scheme
• Private health insurance with AXA Health
• Range of high street, supermarket, restaurant, gym membership, holiday and entertainment discounts via Pluxee
• Employee assistance programme
• Employees are given an additional day of leave for: their wedding and moving house
• Annual leave purchase scheme of up to 10 additional days’ leave per year

If you would like to request any reasonable adjustment, for any part of the recruitment process (including application), please let us know by emailing [e-mail]